3 years ago

Which value of x makes this equation true?

Mathematics

1 answer:

sergejj [24]3 years ago

6 0

Answer:

x=-5

Step-by-step explanation:

opening the bracket on the LHS, we have

-8x-40= -3x+x-7-3

-8x-40= -2x-10

collecting like terms

-8x+2x= -10+40

-6x= 30

divide both sides by -6

x= -5

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The sides of a triangle have lengths of x, x + 5, and 25. If the longest side is 25, which of the following values of x would ma

Amiraneli [1.4K]

In a right angle, the sum of the squares of the two shorter sides is equal to the square of the longest side.
Here, the longest side is 25, the shorter sides are x and x+5.

$x^2+(x+5)^2=25^2 \\
x^2+x^2+10x+25=625 \\
2x^2+10x+25=625 \ \ \ |-625 \\
2x^2+10x-600=0 \ \ \ |\div 2 \\
x^2+5x-300=0 \\
x^2+20x-15x-300=0 \\
x(x+20)-15(x+20)=0 \\
(x-15)(x+20)=0 \\
x-15=0 \ \lor \ x+20=0 \\
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$

The length of a side must be a positive number, so x=15.
The answer is C.

6 0

3 years ago

32.79 divided by 3.1

tiny-mole [99]

Answer:

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7 0

3 years ago

Read 2 more answers

Simplify the following expression 5^2-4/5+2

Sever21 [200]

26 1/5 is the answer i got