Answer:
Step-by-step explanation:
90x - 60y = 68.....multiply by -1
90x - 70y = 91
---------------------------
-90x + 60y = -68 (result of multiplying by -1)
90x - 70y = 91
---------------------------add
-10y = 23
y = -23/10 <===
90x - 60y = 68
90x - 60(-23/10) = 68
90x + 138 = 68
90x = 68 - 138
90x = - 70
x = -70/90
x = -7/9 <=====
[1]
A1 = (h (a + b)) / 2
A1 = (21 (17 + 32)) / 2
A1 = (21 x 49) / 2
A1 = 1,029 / 2
A1 = 514.5 mm²
[2]
A2 = (b x h) / 2
A2 = (11 x 9) / 2
A2 = 99 / 2
A2 = 49.5 mm²
[3]
The area of the shaded region =
A1 - A2 =
514.5 mm² - 49.5 mm² =
465 mm²
The answer is 465 mm².
Average is just the total divided by the number of things you added up.
You've been given 4 numbers.
So just add 7.75+7.25+7.33+7.6 and then divide that by 4.
the answer is therefore 29.93/4
=7.4285
You can check if that seems right by just looking at the numbers, the average will be inbetween the smallest and largest numbers, so it matches up.
3/2 + b = 7/4
First rewrite 3/2 to have the same denominator as 7/4:
3/2 x 2 = 6/4
Now you have 6/4 + b = 7/4
To find b subtract 6/4 from 7/4:
b = 7/4 - 6/4
b = 1/4
17,064. Do multipcation and line numbers up, remember to carry.
