How do you solve for x? What does it equal?
回答 (10)
2009-07-20 5:32 pm
✔ 最佳答案
7x + 29 = -30/xMultiply through by x
7x^2 + 29x = - 30
This is a factorable quadratic. Try to factor. If you can't/won't, use the quadratic formula for the solutions. Don't forget to check your answers in the original equation.
7x^2 + 14x + 15x + 30 = 0
7x(x + 2) + 15(x + 2) = 0
(x + 2)(7x + 15) = 0
x = - 2
and
x = - 15/7
QED
2009-07-20 5:33 pm
7x + 29 = -30/x
Multiply both sides by x:
7x² + 29x = -30
Add 30 to both sides:
7x² + 29x + 30 = 0
Factor:
(7x+15)(x+2) = 0
x = -15/7 and -2 <====Answers
Multiply both sides by x:
7x² + 29x = -30
Add 30 to both sides:
7x² + 29x + 30 = 0
Factor:
(7x+15)(x+2) = 0
x = -15/7 and -2 <====Answers
2009-07-20 5:31 pm
I outlined steps for you in source code. Post there for more help!
2009-07-20 5:30 pm
7x + 29 = - 30/x
Multiply through by x to clear fraction.
7x² + 29x = - 30
Put equation in standard form: ax² + bx + c = 0
7x² + 29x + 30 = 0
Factor using FOIL.
(7x + 15)(x + 2) = 0
x = - 15/7, x = - 2
Multiply through by x to clear fraction.
7x² + 29x = - 30
Put equation in standard form: ax² + bx + c = 0
7x² + 29x + 30 = 0
Factor using FOIL.
(7x + 15)(x + 2) = 0
x = - 15/7, x = - 2
2017-01-20 5:35 am
it quite is 0.5. a million.) You divide x out of the 5x. 2.) Now, in view that is is 10x^2/x. you cancel out the sq.. 10x 3.) Now it quite is user-friendly. 5 = 10x. Divide 10 on the two factors, and you get x = 0.5.
2009-07-20 10:30 pm
7 x^2 + 29 x = - 30
7 x^2 + 29 x + 30 = 0
( 7 x + 15 ) ( x + 2 ) = 0
x = - 15 / 7 , x = - 2
7 x^2 + 29 x + 30 = 0
( 7 x + 15 ) ( x + 2 ) = 0
x = - 15 / 7 , x = - 2
2009-07-20 6:20 pm
7x + 29 = -30/x
x(7x + 29) = -30
7x^2 + 29x + 30 = 0
7x^2 + 15x + 14x + 30 = 0
(7x^2 + 15x) + (14x + 30) = 0
x(7x + 15) + 2(7x + 15) = 0
(7x + 15)(x + 2) = 0
7x + 15 = 0
7x = -15
x = -15/7
x + 2 = 0
x = -2
∴ x = -15/7, -2
x(7x + 29) = -30
7x^2 + 29x + 30 = 0
7x^2 + 15x + 14x + 30 = 0
(7x^2 + 15x) + (14x + 30) = 0
x(7x + 15) + 2(7x + 15) = 0
(7x + 15)(x + 2) = 0
7x + 15 = 0
7x = -15
x = -15/7
x + 2 = 0
x = -2
∴ x = -15/7, -2
2009-07-20 6:02 pm
7x + 29 = -30/ x __ multiply the entire equation by x
x(7x + 29 = -30/x) __ use distributive property of multiplication
7x² + 29x = -30 __ Add 30 to both sides and set equal to zero
7x² + 29x + 30 = 0 __ now factor trinomial into a product of two binomials
(7x + 15)(x + 2) = 0 __ Set each binomial to equal zero
7x + 15 = 0 ---> 7x = -15 ---> x = -15/7
or
x + 2 = 0 ---> x = -2
x(7x + 29 = -30/x) __ use distributive property of multiplication
7x² + 29x = -30 __ Add 30 to both sides and set equal to zero
7x² + 29x + 30 = 0 __ now factor trinomial into a product of two binomials
(7x + 15)(x + 2) = 0 __ Set each binomial to equal zero
7x + 15 = 0 ---> 7x = -15 ---> x = -15/7
or
x + 2 = 0 ---> x = -2
2009-07-20 5:48 pm
I agree with the above answers. they are right!
2009-07-20 5:28 pm
You need to clear the fraction on the right, so multiply everything by x.
7x^2 + 29x = -30
Add 30 to both sides:
7x^2 + 29x + 30 = 0
Now you have a quadratic equation, which you can solve with the quadratic formula. x = [-b +- sqrt(b^2 - 4ac)] / 2a
Edited: I get that b^2 - 4ac = 1, so the solutions don't have any square roots in them.
7x^2 + 29x = -30
Add 30 to both sides:
7x^2 + 29x + 30 = 0
Now you have a quadratic equation, which you can solve with the quadratic formula. x = [-b +- sqrt(b^2 - 4ac)] / 2a
Edited: I get that b^2 - 4ac = 1, so the solutions don't have any square roots in them.
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