7x+(2x+7)=9x+7 show work
Mathematics · Middle School · Tue Nov 03 2020
Answered on
Since there is a + in front of the bracket, we can remove the bracket without changing anything. So we will have:
7x+2x+7=9x+7
9x+7=9x+7
Lets put the variables on one side and the numbers on the other side. Every variable or number that will change signs, will have their sign changed from a + into a - and vice versa.
9x-9x=7-7
0=0
So x equals to infinite because he can take all the values and it wont change anything at all because the x cancels itself.