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2 votes
-5x(4x+6)=21 whats the answer

User Berndinox
by
6.8k points

2 Answers

4 votes
1.) Multiply the parentheses by -5x
2.) Move the constant to the left
3.) Change the signs
4.) Solve the quadratic equation
5.) Evaluate the powers and multiply
6.) Calculate

Answer: No solution
User Glen Selle
by
6.4k points
4 votes

First we must simplify the left side.

-20x² - 30x = 21

We need to move 21 to the left side of the problem, to do that we need to subtract both sides:

-20² - 30x - 21 = 0

Factor -1 out of -20x² - 30x - 21.

So then we have:

- (20x² + 30x + 21) = 0

Our set is: 20x² + 30x + 21 equal to 0 now we must solve for x.

To do that we need to divide.

x = -15 = √195

-----------------------

20

User Skrrgwasme
by
6.9k points
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