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3 years ago

One of the solutions to x2 − 2x − 15 = 0 is x = −3. What is the other solution?

Mathematics

2 answers:

svet-max [94.6K]3 years ago

6 0

<span>x2 − 2x − 15 = 0
</span>(x+3)(x-5) = 0
x +3 = 0 so x = -3
x - 5 = 0 so x = 5

answer is <span>d.x = 5</span>

denis23 [38]3 years ago

6 0

Answer:

x=5

Step-by-step explanation:

One of the solutions to $x^2 - 2x - 15 = 0$ is x = −3

To find out the other solution, we factor the x^2-2x-15

Product is -15 and sum is -2

$-5 \cdot 3 = -15$

$-5+3= -2$

So factors are -5 and 3

$x^2 - 2x - 15 = 0$

$(x-5)(x+3)= 0$

we set each factor =0 and solve for x

$x-5=0, x=5$

$x+3=0, x=-3$

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