4a²=144
a²=144/4
a²=36
a=⁺₋√36
a=⁺₋6
Answer: we have two values for a; a=-6; and a=6
we check it out:
if a=-6
4(-6)²=4*36=144
if a=6
4(6)²=4*36=144
Answer:
225
Step-by-step explanation:
Using the basic components of summation ∑
∑n =
n(n + 1) and ∑1 = n
Thus
∑ (2n - 1) ← for n = 1 to 15
= ∑2n - ∑1
= 2∑n - ∑1
= 2 (
n(n + 1)) - n
= n(n + 1) - n ← Evaluate for n = 15 ( the upper value )
= 15 × 16 - 15
= 240 - 15
= 225