1.
Seven hundred twenty-five
2.
Two hundred thirteen
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>
Just use pemdas
(Parenthesis, exponents, multiplication, division, addition, subtraction)
Answer:
linear and y = 2x + 19
Step-by-step explanation:
the x- values increment by 2 and the values of y increment by 4
This indicates a linear relationship exists in the form
y = mx + c ( m is the slope and c the y-intercept )
m =
=
= 2
y = 2x + c ← is the partial equation
to find c use any ordered pair from the table
using (- 5, 9 ), then
9 = - 10 + c ⇒ c = 9 + 10 = 19
y = 2x + 19 ← linear equation
As a check
x = - 7 : y = - 14 + 19 = 5 ← correct value of y
x = - 5 : y = - 10 + 19 = 9 ← correct value of y
x = - 3 : y = - 6 + 19 = 13 ← correct value of y
x = - 1 : y = - 2 + 19 = 17 ← correct value of y