A speed line L4 passes through E and H. The centres are A and D, with radii 5cm and 4cm respectively. AB = 10cm.
|Mathematics
A speed line L4 passes through E and H. The centres are A and D, with radii 5cm and 4cm respectively. AB = 10cm.
ScanSolve AI Answer
Answer
7.924 cm
Huu hapa ni ufumbuzi wa swali lako:
Sehemu i): Kokotoa urefu wa kamba ya kawaida CD.
Step 1: Weka AM=x.
Katika pembetatu ya kulia △AMC, tunatumia theorem ya Pythagoras:
AC2=AM2+CM252=x2+CM2CM2=25−x2(Eq.1)
Katika pembetatu ya kulia △BMC, BM=AB−AM=10−x. Tunatumia theorem ya Pythagoras:
BC2=BM2+CM282=(10−x)2+CM2CM2=64−(10−x)2(Eq.2)
Step 2: Linganisha Eq. 1 na Eq. 2 ili kupata thamani ya x.
25−x2=64−(10−x)225−x2=64−(100−20x+x2)25−x2=64−100+20x−x225=−36+20x25+36=20x61=20xx=2061=3.05 cm
Step 3: Kokotoa CM na kisha CD.
Tumia x=3.05 cm katika Eq. 1:
CM2=25−(3.05)2CM2=25−9.3025CM2=15.6975CM=15.6975≈3.9620 cm
Urefu wa kamba ya kawaida CD ni mara mbili ya CM:
CD=2×CM=2×3.9620=7.924 cm
Urefu wa kamba ya kawaida CD ni 7.924cm.
Sehemu ii): Kokotoa eneo la eneo lenye kivuli.
Eneo lenye kivuli ni jumla ya maeneo ya sehemu mbili za duara (segments) zinazoundwa na kamba CD. Tunatumia π≈3.142.
Step 4: Kokotoa pembe za katikati (θA na θB).
Kwa duara A (radius rA=5 cm):
Katika △AMC:
cos(∠CAM)=ACAM=53.05=0.61∠CAM=arccos(0.61)≈52.40∘
Pembe ya katikati θA=∠CAD=2×∠CAM=2×52.40∘=104.80∘.
Kwa duara B (radius rB=8 cm):
BM=10−x=10−3.05=6.95 cm.
Katika △BMC:
cos(∠CBM)=BCBM=86.95=0.86875∠CBM=arccos(0.86875)≈29.68∘
Pembe ya katikati θB=∠CBD=2×∠CBM=2×29.68∘=59.36∘.
Step 5: Kokotoa eneo la sehemu ya duara A.
Eneo la sekta CAD:
Eneo la sekta CAD=360∘θA×πrA2=360104.80×3.142×52=360104.80×3.142×25≈22.847cm2
Eneo la pembetatu CAD:
Eneo la △CAD=21×CD×AM=21×(7.924)×(3.05)≈12.084cm2
Eneo la sehemu ya duara A = Eneo la sekta CAD - Eneo la △CAD=22.847−12.084=10.763cm2
Step 6: Kokotoa eneo la sehemu ya duara B.
Eneo la sekta CBD:
Eneo la sekta CBD=360∘θB×πrB2=36059.36×3.142×82=36059.36×3.142×64≈33.150cm2
Eneo la pembetatu CBD:
Eneo la △CBD=21×CD×BM=21×(7.924)×(6.95)≈27.538cm2
Eneo la sehemu ya duara B = Eneo la sekta CBD - Eneo la △CBD=33.150−27.538=5.612cm2
Step 7: Kokotoa jumla ya eneo lenye kivuli.
Jumla ya eneo lenye kivuli = Eneo la sehemu ya duara A + Eneo la sehemu ya duara B
=10.763+5.612=16.375cm2
Eneo lenye kivuli ni 16.38cm2 (kwa sehemu mbili za desimali).
Tuma swali linalofuata 📸
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This mathematics problem involves applying core mathematical principles and formulas. Below you will find a complete step-by-step solution with detailed explanations for each step, helping you understand not just the answer but the method behind it.
ScanSolve AI Answer
Huu hapa ni ufumbuzi wa swali lako: Sehemu i): Kokotoa urefu wa kamba ya kawaida CD. Step 1: Weka AM = x. Katika pembetatu ya kulia AMC, tunatumia theorem ya Pythagoras: AC^2 = AM^2 + CM^2 5^2 = x^2 + CM^2 CM^2 = 25 - x^2 (Eq. 1) Katika pembetatu ya kulia BMC, BM = AB - AM = 10 - x. Tunatumia theorem ya Pythagoras: BC^2 = BM^2 + CM^2 8^2 = (10-x)^2 + CM^2 CM^2 = 64 - (10-x)^2 (Eq. 2) Step 2: Linganisha Eq. 1 na Eq. 2 ili kupata thamani ya x. 25 - x^2 = 64 - (10-x)^2 25 - x^2 = 64 - (100 - 20x + x^2) 25 - x^2 = 64 - 100 + 20x - x^2 25 = -36 + 20x 25 + 36 = 20x 61 = 20x x = (61)/(20) = 3.05 cm Step 3: Kokotoa CM na kisha CD. Tumia x = 3.05 cm katika Eq. 1: CM^2 = 25 - (3.05)^2 CM^2 = 25 - 9.3025 CM^2 = 15.6975 CM = sqrt(15.6975) ≈ 3.9620 cm Urefu wa kamba ya kawaida CD ni mara mbili ya CM: CD = 2 × CM = 2 × 3.9620 = 7.924 cm Urefu wa kamba ya kawaida CD ni 7.924 cm. Sehemu ii): Kokotoa eneo la eneo lenye kivuli. Eneo lenye kivuli ni jumla ya maeneo ya sehemu mbili za duara (segments) zinazoundwa na kamba CD. Tunatumia ≈ 3.142. Step 4: Kokotoa pembe za katikati (_A na _B). Kwa duara A (radius r_A = 5 cm): Katika AMC: ( CAM) = (AM)/(AC) = (3.05)/(5) = 0.61 CAM = (0.61) ≈ 52.40^ Pembe ya katikati _A = CAD = 2 × CAM = 2 × 52.40^ = 104.80^. Kwa duara B (radius r_B = 8 cm): BM = 10 - x = 10 - 3.05 = 6.95 cm. Katika BMC: ( CBM) = (BM)/(BC) = (6.95)/(8) = 0.86875 CBM = (0.86875) ≈ 29.68^ Pembe ya katikati _B = CBD = 2 × CBM = 2 × 29.68^ = 59.36^. Step 5: Kokotoa eneo la sehemu ya duara A. Eneo la sekta CAD: Eneo la sekta CAD = (_A)/(360^) × r_A^2 = (104.80)/(360) × 3.142 × 5^2 = (104.80)/(360) × 3.142 × 25 ≈ 22.847 cm^2 Eneo la pembetatu CAD: Eneo la CAD = (1)/(2) × CD × AM = (1)/(2) × (7.924) × (3.05) ≈ 12.084 cm^2 Eneo la sehemu ya duara A = Eneo la sekta CAD - Eneo la CAD = 22.847 - 12.084 = 10.763 cm^2 Step 6: Kokotoa eneo la sehemu ya duara B. Eneo la sekta CBD: Eneo la sekta CBD = (_B)/(360^) × r_B^2 = (59.36)/(360) × 3.142 × 8^2 = (59.36)/(360) × 3.142 × 64 ≈ 33.150 cm^2 Eneo la pembetatu CBD: Eneo la CBD = (1)/(2) × CD × BM = (1)/(2) × (7.924) × (6.95) ≈ 27.538 cm^2 Eneo la sehemu ya duara B = Eneo la sekta CBD - Eneo la CBD = 33.150 - 27.538 = 5.612 cm^2 Step 7: Kokotoa jumla ya eneo lenye kivuli. Jumla ya eneo lenye kivuli = Eneo la sehemu ya duara A + Eneo la sehemu ya duara B = 10.763 + 5.612 = 16.375 cm^2 Eneo lenye kivuli ni 16.38 cm^2 (kwa sehemu mbili za desimali). Tuma swali linalofuata 📸