And
2. find a solution to the following system of equations.
-5x + 2y = 9
3x + 5y = 7
a (0, 1)
b (-1,2)
c (-9,7)
d (1,7)

x = -1 , y = 2 thus the answer is B

Step-by-step explanation:

Solve the following system:

{2 y - 5 x = 9 | (equation 1)

{3 x + 5 y = 7 | (equation 2)

Add 3/5 × (equation 1) to equation 2:

{-(5 x) + 2 y = 9 | (equation 1)

{0 x+(31 y)/5 = 62/5 | (equation 2)

Multiply equation 2 by 5/31:

{-(5 x) + 2 y = 9 | (equation 1)

{0 x+y = 2 | (equation 2)

Subtract 2 × (equation 2) from equation 1:

{-(5 x)+0 y = 5 | (equation 1)

{0 x+y = 2 | (equation 2)

Divide equation 1 by -5:

{x+0 y = -1 | (equation 1)

{0 x+y = 2 | (equation 2)

Collect results:

 {x = -1 , y = 2

12

step-by-step explanation:

a triangle's   full angle is 180 degrees so 180 - 156 = 24. 24/2=12

step-by-step explanation: