X² + 16x + 64 = 0
x² + 2 * x * 8 + 8² = 0
Now, sing the formula (a + b)² = a² + 2ab + b² , we get,
(x + 8)² = 0
Square rooting on both sides, we get,
x + 8 = √0
x + 8 = 0
x = - 8 <== that's your answer!!!
To convert an angle from degrees to radians, multiply by π/180°.
Your angle is
(-280°)*(π/180°) = -14π/9
The appropriate choice is ...
B) (-14π/9)
2nd one
5th one
are both correct
To find the product of a reasonable estimate of two decimal numbers, round each decimals to the nearest whole number and then perform the multiplication.
For example:
3.2 x 5.7
Estimated answer
3.2 will be rounded down to 3 and 5.7 will be rounded up to 6
⇒ 3 x 6 = 18
Actual Answer
3.2 x 5.7
=18.24