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2 votes
Can someone answer this question please

Can someone answer this question please-example-1

2 Answers

7 votes
The sum of all angles in a triangle is equal to 180°, so....
Equation 1:
(3y-20)+2y+(x+13)=180
5y+x-7=180
x=187-5y

A straight line angle is 180°, so....
Equation 2:
2y+3x+9=180

Substitute x=187-5y into Equation 2:
2y+3(187-5y)+9=180
2y+561-15y+9=180
-13y=-390
y=30

Substitute y=30 into Equation 1:
x=187-5y
=187-5(30)
=37

Answer: x=37°
User Jrhooker
by
5.5k points
6 votes

Answer: C

Explanation:

(x + 13) + (3y - 20) + (2y) = 180 and (2y) + (3x + 9) = 180

so (x + 13) + (3y - 20) + (2y) = (2y) + (3x + 9)

⇒ x + 13 + 3y - 20 = 3x + 9

⇒ x + 3y - 7 = 3x + 9

⇒ 3y = 2x + 16

⇒ y =
(2x+16)/(3)

(2y) + (3x + 9) = 180

2
((2x+16)/(3)) + 3x + 9 = 180


(4x+32)/(3) + 3x = 171

4x + 32 + 9x = 513

13x = 481

x = 37

User Ayende Rahien
by
6.4k points