A triangle has sides with lengths of 5 centimeters, 12 centimeters, and 15 centimeters. Is it a right triangle

No

Step-by-step explanation:

You use the Pythagorean Therom and square your legs (5 and 12) and your hypotenuse (14) it would add up to 25+144=196.

This is not true since 144+25 is 169, not 196

one of each metals

step-by-step explanation:

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15