Question

If a – b = 7 and a + b = 13, what is the value of a2 - b2 =?

Answer 1

pls mark as brainlist pls Mark as brainlist pls Mark as brainlist pls Mark as brainlist pls Mark as brainlist pls Mark as brainlist pls Mark as brainlist pls Mark as brainlist pls Mark as brainlist

Answer 2

The correct answer is 91.

Given: The equations = a – b = 7 and a + b = 13.

To Find: The value of $a^{2} -b^{2} .$

Solution:

a – b = 7 (equation 1)

a + b = 13 (equation 2)

Add equation 1 and 2.

a-b + a+b = 7+13

2a = 20

a = 10

Put the value of a in equation 1.

a - b = 7

10 - b = 7

b = 3

Now put the value of a and b in $a^{2} -b^{2} .$

$a^{2} -b^{2}=10^{2} -3^{2}$

$a^{2} -b^{2}=100-9=91$

Hence, the value of $a^{2} -b^{2}$ is 91.

#SPJ2