Multiply you first equation by 2 to get 4x + 10y = 22
Now the x terms can be eliminated and cancelled out using elimination.
4x + 10y = 22
4x + 3y = 1
To eliminate you need to "subtract", so you need to multiply one of the equations by -1.
4x + 10y = 22
-4x -3y = -1
------------------
0 + 7y = 21
y = 3
Now plug 3 into either one of the equations to get x.
Answer:
The price of pretzels in 1975 = $1.80
Step-by-step explanation:
To answer this question we are assuming the steady rate means linear.Let x be the year and y be the price.
We need to find the slope
m = (y2-y1)/(x2-x1)
= (4.80-4.05)/(2015-2005)
=.75/10
= .075
The slope is .075
We can use the point slope form of the equation
y-y1 = m(x-x1)
y-4.80 = .075(x-2015)
Distribute
y - 4.80 = .075x -151.125
Add 4.80 to each side
y - 4.80+4.80 = .075x -151.125+4.80
y = .075 x - 146.325
We want to find out how much pretzels were in 1975. Put in x=1975
y = .075(1975) -146.325
y = 148.125-146.325
y=1.80
Pi symbol raised to the 3 times x raised to the 4
