So for this, we will be forming a proportion. In this case, our proportion is going to be: . From here we can solve for x.
Firstly, cross-multiply:
Next, divide both sides by 6, and your answer will be (rounded to the whole hour)
The equation that models the balance y after x is y = -145x + 1400
<h3>How to find the equation?</h3>
given that
Zachary uses a payment plan to buy a PC for $1,400. His balance was $820 four months after he made the computer purchase. His amount was $240 eight months after he made the computer purchase.
Assume it has to do with developing an equation that represents this loan as a function of time. Use the loan amount as Y and the time as X.
Now Put that in the standard format:
Y = mX + b
according to the question
at x = 0 then y = 1400
at x = 4 then y = 820
at x = 8 then y = 240
now find the slope
points are (4,820) & (8,240)
slope = -145
now the equation is y = -145x + b
Let x = 4 & y = 820
then
820 = -145(4) + b
820 = 580 + b
b = 820 + 580
b = 1400
finally the equation is
y = -145x + 1400
Learn more about algebraic equations from here::
brainly.com/question/4344214
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2.5 pints. Look it up. That's what I would do
Answer: 1
Step-by-step explanation:
Answer:
x=-2 and y=2
Step-by-step explanation:
Do simultaneous equations
-8x + 4y = 24 <em>(multiply everything in the equation by -7)</em>
-7x + 7y = 28 <em>(multiply everything in the equation by 8)</em>
56x - 28y = -168
-56x + 56y = 224
<em>(add equations, ie add 'x' parts, 'y' parts, and numerical parts)</em>
<em> </em>28y = 56
∴y = 2
-8x + 4y = 24
-8x + 4(2) = 24
-8x = 16
∴x=-2
Lemme know if you have questions :D