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Which of the following are solutions to the quadratic equation? Check all that

apply.
2x2 + 5x -10 = x2 + 4

User Sunhwa
by
4.6k points

2 Answers

3 votes

Answer:

x = 2 or x= -7

Explanation:

We can use factorisation to solve this.

First, we shift all the variables to one side (see attachement)

Then, we need to find the value of x, which multiples to give -14 and adds together to give 5.

7 - 2 = 5

and 7 x (-2) = -14.

Now we factorize (group into brackets) to find the values of x.

We solve for x to find the final answer.

Which of the following are solutions to the quadratic equation? Check all that apply-example-1
User ChiliYago
by
4.7k points
2 votes

Answer:

Explanation:

2x2+5x−10=x2+4

Step 1: Subtract x^2+4 from both sides.

2x2+5x−10−(x2+4)=x2+4−(x2+4)

x2+5x−14=0

For this equation: a=1, b=5, c=-14

1x2+5x+−14=0

Step 2: Use quadratic formula with a=1, b=5, c=-14.

x=

−b±√b2−4ac

2a

x=

−(5)±√(5)2−4(1)(−14)

2(1)

x=

−5±√81

2

x=2 or x=−7

Answer:

x=2 or x=−7

User Aaront
by
5.1k points