Answer:
x=-2
y= 8
Step-by-step explanation:
Given data
10x – 2y = -36-----------1
7x – 2y = -30--------------2
-Subtract to eliminate y
3x-0= -6
3x= -6
x= -6/3
x= -2
Put x= -2 in
7(-2)– 2y = -30
-14-2y=-30
-14+30=2y
16=2y
y= 16/2
y= 8
Simply it as follows:
1 + 39 = 40
2 + 38 = 40 etc
18 + 22 = 40
19 + 21 = 40
There are 19 of these plus 40 itself . . .therefore 20 of them
20 x 40 = 800
And finally the last number not used, 20
Therefore 800 + 20 = 820
Answer:
1
Step-by-step explanation:
1
r = √(3V/πh)
multiply both sides by 3 to eliminate the fraction
πr²h = 3V ( divide both sides by πh )
r² = 3V/ πh ( take the square root of both sides )
r = √(3V/πh)
