How do you solve #9a + 15 =10a - 7#?

1 Answer
May 31, 2016

Answer:

#a=22#

Explanation:

Given,

#9a+15=10a-7#

Subtract #9a# from both sides.

#9acolor(white)(i)color(red)(-9a)+15=10acolor(white)(i)color(red)(-9a)-7#

#15=a-7#

Add #7# to both sides.

#15color(white)(i)color(red)(+7)=a-7color(white)(i)color(red)(+7)#

#a=color(green)(|bar(ul(color(white)(a/a)color(black)(22)color(white)(a/a)|)))#