If a= 3 and b= -1, what is the value of ab-b’2?

a x b = -3. b x b = 1. Now whats -3 - 1? When a letter is right next to another letter without a space, that means it wants you to multiply the value of one letter by the other. for example, if x equals 2 and y equals 3, and they're right next to each other like this: xy that means you need to multiply x by y. X times Y = 2 times 3. 2x3=6. If you see a letter with a small number beside it, this means that it wants you to multiply the value of that letter by itself times the little number on the top. For example, if n equals 6, and the little number on the top right is 3, then that means you have to multiply 6 by 6 three times. 6 x 6 x 6 = 216.

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