Help with algebra problems!

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Help with algebra problems!

Need major help;
Factoring
1.) x^2+7x-30=0
2.) 2x^2+x=10
graphing (please include points)
3.) y=x^2-3
4.) y>4x^2-8x+7
solve
5.) x^2-12x+1=0
6.) 3x^2-12x=-1
7.) x^2+3x=4
8.) 2x^2+4x-4=0
Please help
Please include details/show work
All answers are appreatiated.
AlgebraHouse AlgebraHouse
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Re: Help with algebra problems!

Factoring
1.) x^2+7x-30=0
(x + 10)(x - 3) = 0 {factored into two binomials}
x + 10 = 0 or x - 3 = 0 {set each factor equal to 0}
x = -10 or x = 3 {solved each equation for x}

2.) 2x^2+x=10
2x² + x - 10 = 0 {subtracted 10 from both sides}
(2x + 5)(x - 2) = 0 {factored into two binomials}
2x + 5 = 0 or x - 2 = 0 {set each factor equal to 0}
2x = -5 or x = 2 {subtracted 5 and added 2, respectively}
x = -5/2 or x = 2 {divided by 2 in first equation}

graphing (please include points)
3.) y=x^2-3
4.) y>4x^2-8x+7
There is a graphing calculator on this site:
Graphing Calculator


solve
5.) x^2-12x+1=0
use the quadratic formula on this a = 1, b = -12, and c = 1

6.) 3x^2-12x=-1
3x² - 12x + 1 = 0 {added 1 to both sides}
substitute into the quadratic formula: a = 3, b = -12, c = 1

7.) x^2+3x=4
x² + 3x - 4 = 0
(x + 4)(x - 1) = 0 {factored into two binomials}
x + 4 = 0 or x - 1 = 0 {set each factor equal to 0}
x = -4 or x = 1 {solved each equation for x}

8.) 2x^2+4x-4=0
2(x² + 2x - 2) = 0 {factored out the greatest common factor, 2}
x² + 2x - 2 = 0 {set that in parentheses equal to 0}
use the quadratic formula: a = 1, b = 2, c = -2

Remember, if you can't factor the trinomial in the quadratic equation,
you need to use the quadratic formula.

- Algebra House