Find the value of each of the variables. A X = 12, y = 15, z = 20
B. X = 9,7 = 15,2 - 20
C. X = 9,y = 18,2 = 20
D. X = 12, y = 18,2 = 20

B

Step-by-step explanation:

B

yes the total will be same because in both of them the expression.is rearranged but their sign remains the same hence it hss just been shuffled

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