Let 11x + 15y + 23 = 0 be equation (1)
And 7x - 2y - 20 = 0 be equation (2)
Multiply equation (1) by 2:
22x + 30y + 46 = 0
Multiply equation (2) by 15:
105x - 30y - 300 = 0
Add equations (1) and (2):
22x + 105x + 30y - 30y + 46 - 300 = 0
127x - 254 = 0
127x = 254
x = 254/127
[x = 2]
Substitute x = 2 in equation (1) to find y:
11(2) + 15y + 23 = 0
22 + 15y + 23 = 0
15y + 45 = 0
15y = -45
y = -45/15
y = -3
Therefore, x = 2 and y = -3.
Answer:
400 ping pong balls
Step-by-step explanation:
Let the total number of ping pong balls =x
Out of x ping pong balls, 80 are marked with a blue dot
Out of 80 ping pong balls, 16 are marked with a blue dot.
Expressing it as a ratio:
x:80=80:16

There are an estimate of 400 ping pong balls in the container.
A. An organ is the oldest keyboard instrument.
Answer:
A cone has one -third times the volume of a cylinder with the same base and altitude. <u>True</u>