Answer:
x = -9, -3
Step-by-step explanation:


x = -3, -9
Answer:
x = 30
Step-by-step explanation:
2x + 90° + x = 180°
3x + 90° = 180°
3x = 90°
x = 90/3
x = 30
Answer:
32x
Step-by-step explanation:
Distribute the -8x to the (-4)
8x+15=7
In the statement the phrase the sum of can tell you that it is going to be an addition problem. So 8x ( eight times a number) would be added to the 15, 8x+15. Since its an addition problem the part where it says ' ... is seven', you know that it will all equal 7. So the answer would be 8x+15=7.