Question

If (a - b) = 4; ab = 26.25; then (4a- 462) = ?
1) 484
2) 192
3) 160
4) 176
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Answer 1

Step-by-step explanation:

a-b=4

b=a-4

ab=26.25

a(a-4)=26.25

a^2-4a-26.25=0

by quadratic formula

a= ( 4(+/-)√121)/2

a=-7/2or15/2

a=15/2 as a= -7/2 isn't admissible

4a-462=4(15/2)-462

=-432