Evaulate 9÷3[(20-7) -2to the power of 2]

27

Step-by-step explanation:

Evaulate 9÷3[(20-7) -2to the power of 2]

9÷3[(20-7) - 2²]

9 ÷ 3 = 3

[(20-7) - 2²] = (13 - 4) = 9

Hence ;

9÷3[(20-7) - 2²]

3(9)

= 27

step-by-step explan mxfcg'k; uafwgzfgjhklhgation:

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