Answer:
72 degrees
Step-by-step explanation:
the temperature rose 15, and ended as 87, so the temp was 72 before it rose
I think it should also be 16 but I’m not pretty sure so hopefully you get it right !
It takes 7 hours to mow 4 lawns
Therefore every hour, (4 ÷ 7) or 4/7 lawns are mowed. This gives the rate.
For 35 hours, 4/7 x 35 lawns are mowed.
=35 ÷ 7 = 5
= 4 × 5
= 20 lawns
If you want to solve this problem using formulas, there are two important formulas:
t1 = first term = -5
tn = nth term = last term = -5
n = numbr of terms
Sn = sum of the n terms
tn = t1 + (n - 1)d ---> 65 = -5 + (n - 1)(5)
65 = -5 + 5n - 5
65 = -10 + 5n
75 = 5n
n = 15
Sn = n(t1 + tn)/2 ---> Sn = 15(-5 + 65)/2
Sn = 450
So ur answer rounds up to 450
Letter c
:)
hope i helped
~Luis
Answer:
Step-by-step explanation:
1). x² - 10x + a²
By using the formula of (a - b)² = a² - 2ab + b²
x² - 2(5)x + a²
Therefore, for a perfect square of the expression a should be equal to 5.
Therefore, (x² - 10x + 25) will be the answer.
2). x² + 2ax + 36
= x² + 2(a)x + 6²
For a perfect square of the given expression value of a should be 6.
x² + 2(a)x + 6² = x² + 2(6)x + 6²
= (x + 6)²
Therefore, x² + 12x + 36 will be the answer.
3). ![x^{2}+\frac{1}{2}x+a^2](https://tex.z-dn.net/?f=x%5E%7B2%7D%2B%5Cfrac%7B1%7D%7B2%7Dx%2Ba%5E2)
![x^{2}+2(\frac{1}{4})x+a^2](https://tex.z-dn.net/?f=x%5E%7B2%7D%2B2%28%5Cfrac%7B1%7D%7B4%7D%29x%2Ba%5E2)
To make this expression a perfect square,
a² = ![(\frac{1}{4})^2](https://tex.z-dn.net/?f=%28%5Cfrac%7B1%7D%7B4%7D%29%5E2)
= ![(x+\frac{1}{4})^2](https://tex.z-dn.net/?f=%28x%2B%5Cfrac%7B1%7D%7B4%7D%29%5E2)
Therefore, the missing number will be
.