For problems like this you can move the y's on the bottem up top by fliping the sign of the exponent (in this case 7 to -7) and MULTIPLYING it with EVERYTHING on top, then because of properties of multplication you can add the exponents to combine them into one term (in this case add 3 and -7 to get -4)

If any of this does not make sense let me know and ill try to clarify better
Answer:
<u>The number of pens = 120 and the number of pencils = 200</u>
Step-by-step explanation:
Let the number of pens x, and the number of pencils is y
the cost of one pen $1, and the cost of one pencil $0.5
The cost of the whole purchase was $220
1 * x + 0.5 * y = 220
x + 0.5 y = 220 ⇒ eq.(1)
there were 80 more pencils than pens
y - x = 80 ⇒ eq.(2)
from eq.(2) x = y - 80
By substitution with x from the last equation at eq.(1)
∴ (y - 80) + 0.5 y = 220
1.5y = 220 + 80 = 300
y = 300/1.5 = 200
x = y - 80 = 200 - 80 = 120
<u>So, the number of pens = 120 and the number of pencils = 200</u>
This set notation really seems the hard way to exclude a single value. Anyway...
The domain doesn't include where the denominator is zero, 4x + 7 = 0,
x = -7/4
The range doesn't include the asymptotic value, which is
y=2x/4x = 1/2
So we need domain x ≠ -7/4 and range y ≠ 1/2
Answer: First choice
Answer:
There must he a circulation. May not be causation.
Answer:
1
Step-by-step explanation:
if there is just k, the number behind it is always 1