Answer:
8°
Explanation:
The laws of angles say that angles opposite the vertex (as in this case) are equal
So
(7x + 15)° = (9x - 1)°
let's remove the ° just so as not to get confused
7x + 15 = 9x - 1
To solve we must move the Xs on one side of the = sign and the free numbers on the other. For that, we must do the same operations on both sides. If we subtract from one, from the other also, and so on.
So we are going to substract 15
(7x + 15) - 15 = (9x - 1) -15
It result:
7x = 9x - 16
We are going to substract 9x
(7x) - 9x = (9x - 16) - 9x
It result:
7x - 9x = -16
-2x = -16
We are going to change the signs (ON BOTH SIDES)
2x = 16
x = 8
now we have the value of X
we substitute x in the equations
7(8) + 15 = 9(8) - 1
56 + 15 = 72 - 1
71 = 71
So, the angles are 71°
And the Value of X is 8°