X^2 - x - 20
(x + 4)(x - 5) <==
x^2 - x - 20.....the last sign, which is negative, tells me that one set is positive and one set is negative. The first sign, which is also negative, tells me that the larger number will be negative. Now u have to find 2 numbers, that when added equal -1 and when multiplied, equal -20....those numbers are -5 and 4. so ur answer is : (x + 4)(x - 5)
The radius of the circle is and the length of the chord is . The angle subtended by the chord CD at the center of the circle is
.
Therefore, the measure of arc CD is
Percentage error is calculated by
Percentage error = (estimate-real)/real*100%=(115-82.5)/82.5*100%=28.26%
An over-estimate gives a positive error percent, and an underestimate gives a negative error.
Also, dividing by the real value makes it possible to have more than 100% error.
For example, if real cost is $50, and estimated cost is $150, then error percent is (150-50)/50*100%=200%!