Step-by-step explanation:
for a
- a+,38°=90°{ angle at circumference through center is 90°}
- a=90-38
- a=52°
for e
- e=38°{base angle of isosceles triangle r equal}
for d
- 38°+e+d=180°{sum of angle of triangle}
- d=180-76
- d=104°
for. c
- c+d=180°{straight angle}
- c=180-104°
- c=76°
for b
- a+b+c=180°{sum of angle of triangle}
- b=180-128
- b=52°
hope it helps.
<h2>stay safe healthy and happy.</h2>
Answer: the 4th one I think
Step-by-step explanation:
U can round 289 to 290 and round 7 to 5 or 10
We have that
<span>sin (7π/12)=?
we know that
</span>7π/12=(π/4+π/3)
and
<span><span>sin<span>(A+B)</span>=sin<span>(A)</span>cos<span>(B)</span>+cos<span>(A)</span>sin<span>(B)
then
</span></span>sin(π/4+π/3)=sin(π/4)cos(π/3)+cos(π/4)sin(π/3)
sin(π/4+π/3)=(√2/2)(1/2)+(√2/2)(√3/2)-------> (√2/4)+(√6/4)---> (√2+√6)/4
the answer is (√2+√6)/4
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