How do you solve $-3( x - 5) ^ { 2} = - 18$ ?

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Answer 1 · 2018-03-14T17:26:11

Solution in explanation:

Expand $(x-5)^2$ :

$-3[(x-5)(x-5)=-18$

$-3[x^2-10x+25]=-18$

Multiply by -3:

$-3x^2+30x-75=-18$

[Be careful of signs when multiplying.]

Adding $18$ to both sides:

$-3x^2+30x-75+18=-18+18$

$-3x^2+30x-57=0$

Solve:

$x=5-$ $root$ 6 $or x=5+$ $root$ 6

How do you solve -3( x - 5) ^ { 2} = - 18-3( x - 5) ^ { 2} = - 18?