When you use a tens fact you round to the nearest ten and 15-8=7. The nearest ten to seven is 10
Answer:10
The correct answer is C
Hope this helped :)
3x+7=-x-1
move -x to the other side
sign changes from -x to +x
3x+x+7=-x+x-1
3x+x+7=-1
4x+7=-1
move 7 to the other side
sign changes from +7 to -7
4x+7-7=-1-7
4x=-8
Divide by 4 for both sides
4x/4=-8/4
Answer: x=-2
Well, it will be forming Linear Pair. So,
130+3x+5 = 180
3x = 45
x = 15
