How do you solve 7+8x=12 algebraically and graphically?

2 Answers
Jul 3, 2018

The solution is x=17

Explanation:

The equation is

7+8x=12

, 8x=127=5

Squaring both sides

(8x)2=52

, 8x=25

, x=8-25=-17

Graphically, plot the curve

8x+712=0

8x5=0

graph{sqrt(8-x)-5 [-30.25, 10.3, -8.68, 11.58]}

And the solution to the equation is the point where the curve intercepts with the x-axis, that is (17,0)

Jul 3, 2018

I tried this:

Explanation:

1) Algebraically:
rearrange:

8x=127

8x=5

square both:

(8x)2=52

8x=25

x=25+8=17

2) Graphically:
graph{(y-7-sqrt(8-x))(y-12)=0 [-50.02, 14.96, -3.34, 29.11]}