Simplify. Note the equal sign. What you do to one side, you do to the other. Follow PEMDAS.
Isolate the x.
First, distribute 6 to all terms within the parenthesis
6(-3) = -18
6(4x) = 24x
7x - 18 + 24x = 199
Simplify. Combine like terms
31x - 18 = 199
Isolate the x. Add 18 to both sides
31x - 18 (+18) = 199 (+18)
31x = 199 + 18
31x = 217
Isolate the x. Divide 31 from both sides
31x/31 = 217/31
x = 217/31
x = 7
7 is your answer for x
hope this helps
16 n^2 -10n + 129 = 8n^2 -8
We collect the terms:
8n^2 -10n + 137 = 0
The steps for completing the square:
1) Move the "non X" (or "non N") term to the right:
8n^2 -10n = -137
<span>2)<span> Divide the equation by the coefficient of N² which in this case is 8
n^2 -1.2n = </span></span><span><span>-17.125
</span>
3) Take the coefficient of "N"; divide it by 2; square it; add it to both sides of the equation.
-1.2 / 2 = -.6
-.6^2 = .36
</span>
n^2 -1.2n +.36 = <span>-17.125
+.36
Take the square root of both sides:</span>
(n-.6)*(n-.6) = sq root(
<span>
<span>
<span>
-16.765
</span>
</span>
</span>
)
That's about as far as I can go.
You solve this by plugging one equation into the other. Usually you have to rewrite one equation to make this work. In this case I choose to rewrite y-4x=0 as y=4x.
After plugging it into the second, you get:
3x + 6*4x = 9 => 27x = 9 => x=1/3
Putting this solution back into y=4x gives us y=4/3
I did the work for you. I also showed my work. Hope it helped