Today I got headaching questions from other subjects and my mind has stopped!☠️ Question number 7, 13, and 16 please

7a) 5/8 cup

7b) 4  3/8 cup

Step-by-step explanation:

a) Divide 1 1/4 by 2:

Do this by putting the 1 into the fraction and then convert to 8th

1 1/4 = 5/4 = 10/8

(10/8)/2 = 5/8

b) 3 1/2 * 1 1/4 = 7/2 * 5/4 = 7*5/(2*4) = 35/8 = 4 3/8

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