If y = 5x^2 - 2x, and x = 3, then y = ?

Question

If  y = 5x^2 - 2x , and  x = 3 , then  y =  ?

(A) 24
(B) 27
(C) 39
(D) 51
(E) 219

Catman · Answer

Put x=3 in the equation y = 5x^2 - 2x

y= (5*3*3)-(2*3)

y= 45-6

y= 39.

option C.

asad9242 · Answer

y=5x^2−2x
x=3
y=5*9-2*3
y=45-6=39

matchatea · Answer

if x is 3 
Then,
y = 5 *3*3 - 2*3 
y = 45 -6
So y is 39.
Option C is correct

henokgadissa · Answer

Direct substitution the value of x
y=5(3)^2 -2(3)=45-6=39

Therefore, the answer will be C:39

subhashsavalia · Answer

y= x(5x-2)= 3(5*3-2)= 3*13=39.. Need not to go for squaring and large substraction.

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