How do you solve 3x+8=x+2?

2 Answers
Mar 11, 2016

x={3,12}

Explanation:

3x+8=x+2
3x=x+28
3x=x6
(3x)2=(x6)2
3x=x212x+36
x212x3x+36=0
x215x+36=0
(x12)(x3)=0
if (x-12)=0 then x=12
if (x-3)=0 then x=3
x={3,12}

Mar 11, 2016

3 and 12

Explanation:

3x+8=x+2
Isolate the radical term.
3x=x6
Square both sides:
3x=(x6)2=x212x+36
x215x+36=0
Find 2 numbers (real roots) knowing sum (15 = -b) and product (c = 36). They are: 3 and 12.