How do you solve #3a + (2a - 5) = 13 - 2(a + 2 )#?

2 Answers
Mar 20, 2018

Answer:

#a=14/7#

Explanation:

#3a+(2a-5)=13-2(a+2)#
#3a+(2a-5)=13-(2a+4)#
#3a+2a-5=13-2a-4#
#5a-5=9-2a#
#5a+2a=9+5#
#7a=14#
#a=14/7#

Mar 20, 2018

Answer:

#a=2#

Explanation:

#"distribute parenthesis on both sides of the equation"#

#3a+2a-5=13-2a-4#

#"collect like terms on both sides"#

#rArr5a-5=9-2a#

#"add 2a to both sides"#

#5a+2a-5=9cancel(-2a)cancel(+2a)#

#rArr7a-5=9#

#"add 5 to both sides"#

#7acancel(-5)cancel(+5)=9+5#

#rArr7a=14#

#"divide both sides by 7"#

#(cancel(7) a)/cancel(7)=14/7#

#rArra=2#

#color(blue)"As a check"#

Substitute this value into the equation and if both sides are equal then it is the solution.

#"left "=6+(-1)=6-1=5#

#"right "=13-2(4)=13-8=5#

#rArra=2" is the solution"#