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the school store sells binders for $4.00 each and pens for $2.00 each the equation in standard form is 4x+2y=20 it describes the number of binders x and pens y that you can buy for $20complete the table to show the possible combinations of binders and pens that can be bought for $20I really need help

the school store sells binders for $4.00 each and pens for $2.00 each the equation-example-1
User Nobeh
by
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1 Answer

3 votes

(0,10), (1,8), (2,6), (3,4), (5,2), (6,-2)

Step-by-step explanation


4x+2y=20

Step 1

subtract 4x in both sides


\begin{gathered} 4x+2y=20 \\ 4x+2y-4x=20-4x \\ 2y=20-4x \end{gathered}

Step 2

divide each side by 2


\begin{gathered} (2y)/(2)=(20)/(2)-(4x)/(2) \\ y=\text{ 10-2x Equation(1)} \end{gathered}

Step 3

replace the value of x in equation (1) starting with 0 (table)


\begin{gathered} \text{when x=0} \\ y=10-2x=10-2(0)=10-0=10 \\ \text{then, when x= 0, y=}10 \end{gathered}

point(0,10)


\begin{gathered} \text{when x= 1} \\ y=10-2x=10-2(1)=10-2=8 \\ (1,8) \end{gathered}

point(1,8)


\begin{gathered} f(1)=10-2(1)=10-2=8 \\ f(2)=10-2(2)=10-4=6 \\ f(3)=10-2(3)=10-6=4 \\ f(4)=10-2(4)=10-8=2 \\ f(5)=10-2(5)=10-10=0 \\ f(6)=10-2(6)=10-12=-2 \end{gathered}

I hope this helps you

User Zach Scrivena
by
8.2k points
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