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If x2+x=20, which of the following is true?
A x2−x<10x2−x<10
B 10 C 11 D 31

User Tounaobun
by
2.8k points

2 Answers

2 votes

Final answer:

To solve the equation x^2 + x = 20, we can use the quadratic formula. The solutions are x = 4 and x = -5. Therefore, none of the options listed (A, B, C, D) are true. The correct solutions to the equation x^2 + x = 20 are x = 4 and x = -5.

Step-by-step explanation:

The given equation is x^2 + x = 20. To solve this equation, we can start by rearranging the terms to get x^2 + x - 20 = 0. This is a quadratic equation, and it can be solved by factoring, completing the square, or using the quadratic formula. Let's use the quadratic formula.

The quadratic formula is x = (-b ± √(b^2 - 4ac)) / (2a),

where a, b, and c are the coefficients in the quadratic equation ax^2 + bx + c = 0.

In this case, a = 1, b = 1, and c = -20.

Plugging these values into the quadratic formula, we get x = (-1 ± √(1^2 - 4(1)(-20))) / (2(1)).

Simplifying further, x = (-1 ± √(1 + 80)) / 2. x = (-1 ± √81) / 2. x = (-1 ± 9) / 2.

So the solutions to the equation are x = (-1 + 9) / 2 = 4 and x = (-1 - 9) / 2 = -5.

Therefore, none of the options listed (A, B, C, D) are true. The correct solutions to the equation x^2 + x = 20 are x = 4 and x = -5.

User KnuturO
by
3.5k points
9 votes

Answer:

Answer is A probably

Step-by-step explanation:

X2-x=20-2x

On comparison we can figure that out

Still I'm a 8th grader so my answer can be wrong

User Venkatesh A
by
3.2k points