Mathematics
The value (values) of x satisfying the equation x2 - 6x - 16 = 0 is/are :
8 or -2
-8 or 2
8 and -2
-8 or 2
Quadratic Equations
11 Likes
Answer
Comparing equation x2 - 6x - 16 = 0 with ax2 + bx + c = 0, we get :
a = 1, b = -6 and c = -16.
By formula,
x =
Substituting values we get :
Substituting x = 8 in L.H.S. of equation x2 - 6x - 16 = 0, we get :
⇒ 82 - 6(8) - 16
⇒ 64 - 48 - 16
⇒ 0.
Substituting x = -2 in L.H.S. of equation x2 - 6x - 16 = 0, we get :
⇒ (-2)2 - 6(-2) - 16
⇒ 4 + 12 - 16
⇒ 0.
Since, L.H.S. = R.H.S., thus x = -2 is a solution of the equation.
Thus 8 and -2 are the solution of the equation x2 - 6x - 16 = 0.
Hence, Option 3 is the correct option.
Answered By
7 Likes
Related Questions
If x2 - 8x - 9 = 0; values of x correct to one significant figure are :
9 and -1
9 or -1
9.0 or -1.0
9.00 or -1.00
If x2 - 2x - 3 = 0; values of x correct to two significant figures are :
3.0 and 1.0
-1.0 and 3.0
3.0 or -1.0
3.00 or -1.00
Solve the following equation for x and give your answer correct to one decimal place :
x2 - 8x + 5 = 0
Solve the following equation for x and give your answer correct to one decimal place :
5x2 + 10x - 3 = 0