Question

if a + b = 1 and a - b = 7 find
I. 5 (a^2 + b^2) [ans=125]
ii. ab [ans=12]
How?
Pls ans fast urgent i will mark brainliest

Answer 1

Step-by-step explanation:

given a+b=1->eq1

a-b=7->eq2

eq1+eq2

a=4

eq1-eq2

b=-3

i.5(a^2+b^2)=5(4^2+(-3)^2)

=5(16+9)

= 5(25)=125

ii.ab=4(-3)

= -12