#1**+10 **

Hmm... To me, this looks like maybe homework? Instead of giving you the answer, here are some hints:

Add the last two equations together, what do you get?

ilorty Jul 21, 2020

#2**+1 **

From the second equation b = a+7 sub this into the third equation ...then solve for 'a'

use this value of 'a' in equation 2 or three to find 'b'

then use the values of 'a' and 'b' in equation 1 to find 'c'

ElectricPavlov Jul 21, 2020