The sum of the ages of Devin and Maggie is 96 years. 8 years ago, Devin's age was 4 times Maggie's age. How old is Devin now?

72years old

Step-by-step explanation:

Let Devin's age be x

Let Maggie present age be y

If the sum of the ages of Devin and Maggie is 96 years, then;

x+y = 96 1

If by 8 years ago, Devin's age was 4 times Maggie's age, then;

Devin = x - 8

Maggie = y - 8

x-8 = 4(y-8)

x-8 = 4y - 32 ...2

From 1;

x = 96 - y..3

Substitute 3 into 2

96-y - 8 = 4y - 32

-y-4y = -32 - 88

-5y = -120y

y = 120/5

y = 24

Since x = 96-y

x = 96 - 24

x = 72years

Hence Devin will be 72years old now

none of the option is correct.

step-by-step explanation:

it says to find which expression equals 9^3 sqrt 10 = ?

9^3 sqrt 10 = 729 sqrt 10.

checking option a. 5 sqrt 10 + 4 sqrt 10

5 sqrt 10 + 4 sqrt 10

= 9 sqrt 10.

checking option b. 5^3 sqrt 10 + 4^3 sqrt 10

5^3 sqrt 10 + 4^3 sqrt 10

= 125 sqrt 10 + 64 sqrt 10

= 189 sqrt 10.

checking option c. 5 sqrt 10 + 4^3 sqrt 10

5 sqrt 10 + 4^3 sqrt 10

= 5 sqrt 10 + 64 sqrt 10

= 69 sqrt 10.

checking option d. 5^3 sqrt 10 + 4 sqrt 10

5^3 sqrt 10 + 4 sqrt 10

= 125 sqrt 10 + 4 sqrt 10

= 129 sqrt 10.

hence, none of the option is correct.