Given:
Three numbers in an AP, all positive.
Sum is 21.
Sum of squares is 155.
Common difference is positive.
We do not know what x and y stand for. Will just solve for the three numbers in the AP.
Let m=middle number, then since sum=21, m=21/3=7
Let d=common difference.
Sum of squares
(7-d)^2+7^2+(7+d)^2=155
Expand left-hand side
3*7^2-2d^2=155
d^2=(155-147)/2=4
d=+2 or -2
=+2 (common difference is positive)
Therefore the three numbers of the AP are
{7-2,7,7+2}, or
{5,7,9}
Answer:
4 4√3
Step-by-step explanation:
15 / 21 = 75 / x.....15 shots to 21 grams = 75 shots to x grams
cross multiply
(15)(x) = (75)(21)
15x = 1575
x = 1575 / 15
x = 105 grams <===
C). (3, 29) would be your answer.
Explanation?:
Rewrite the equation in vertex form.
y = -3(x - 3)^2 + 29
use the vertex form, y = a(x - h)^2 + k, to determine the values of a, h, and k.
a = -3
h = 3
k = 29
The vertex = (h, k)/(3, 29)
Hope this helps!
Answer:
Your answer is 9
Step-by-step explanation:
√9=3
3-7=-4