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navik [9.2K]
4 years ago
6

WILL MARK BRAINLIEST Harry had $32. He spent all the money on buying 3 notebooks for $x each and 4 packs of index cards for $y e

ach. If Harry had bought 5 notebooks and 5 packs of index cards, he would have run short of $18. A student concluded that the price of each notebook is $5 and the price of each pack of index cards is $1. Which statement best justifies whether the student's conclusion is correct or incorrect? The student's conclusion is incorrect because the solution to the system of equations 3x + 4y = 32 and 5x + 5y = 50 is (8, 2). The student's conclusion is incorrect because the solution to the system of equations 3x + 4y = 32 and 5x + 5y = 18 is (8, 2). The student's conclusion is correct because the solution to the system of equations 3x + 4y = 32 and 5x + 5y = 18 is (5, 1). The student's conclusion is correct because the solution to the system of equations 3x − 4y = 32 and 5x − 5y = 50 is (5, 1).
Mathematics
2 answers:
forsale [732]4 years ago
6 0
The student's conclusion is incorrect because the solution to the system of equations 3x + 4y = 32 and 5x + 5y = 50 is (8, 2). <span>
</span>
kkurt [141]4 years ago
3 0

Answer:

The student's conclusion is incorrect because the solution to the system of equations 3x + 4y = 32 and 5x + 5y = 50 is (8, 2).

Step-by-step explanation:

To see if the answer to an equation is right, you just have to put the value of X and Y into the equation system, since we don´t have the equation system that the student used, we will make our own, so we will start by stating that Notebooks are represented by X and index cards are represented by Y.

Your equation would look like this:

3x+ 4y=34

The student said that the price of the notebook is $5 and the index card would be $1, now we put those values into the equation.

3(5)+4(1)=32

15+4=32

19=32

Since 19 is not equal to 32, the equation is wrong, therefore the student is wrong.

Now to solve it you get your other equation, since if he had bought 5 and 5 he would have needed 18 extra dollars that means that

5x+5y= 32 +18

5x+5y=50

With the two equations you just use elimination process to create a single equation:

(5x+5y=50)-3=  -15x-15y=-150

(3x+4y=32)5 =   15x+20y= 160

You eliminate the x from the equation and are left with:

-15y+20y= -150+160

5y=10

y=\frac{10}{2}

y=2

Now that you have the value of Y you just put it into the equation to know the value of x:

5x + 5(2) = 50

5x+10=50

You clear the x and the result would look like this:

x= \frac{50-10}{8}

x=8

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