9514 1404 393
Answer:
$2.50
Step-by-step explanation:
The question asks for the total cost of a notebook and pen together. We don't need to find their individual costs in order to answer the question.
Sometimes we get bored solving systems of equations in the usual ways. For this question, let's try this.
The first equation has one more notebook than pens. The second equation has 4 more notebooks than pens. If we subtract 4 times the first equation from the second, we should have equal numbers of notebooks and pens.
(8n +4p) -4(3n +2p) = (16.00) -4(6.50)
-4n -4p = -10.00 . . . . . . . . . . . simplify
n + p = -10.00/-4 = 2.50 . . . . divide by the coefficient of (n+p)
The total cost for one notebook and one pen is $2.50.
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<em>Additional comment</em>
The first equation has 1 more notebook than 2 (n+p) combinations, telling us that a notebook costs $6.50 -2(2.50) = $1.50. Then the pen is $2.50 -1.50 = $1.00.
One could solve for the costs of a notebook (n) and a pen (p) individually, then add them together to answer the question. We judge that to be more work.
Answer:
400mL/3l
Is the correct answer
Step-by-step explanation:
Answer:
36 = 2² x 3²
72=2³×3²
Step-by-step explanation:
Write the 2 equations:
5x-2y=18
-5x+3y=-22
You can see that the coefficients of x are opposites, so you can add them(the 2 equations) to eliminate x.
Adding them, you get:
y=-3
So now that you know y, you can substitute the value of y into one of the original equations. Let's substitute it in the first one:
5x+6=18
Solving this, we get:
5x=12
x=12/5
x=12/5, y=-3
Answer:
A 25% tip on a bill of $68.28 rounded to $70 would be <u>$17.50</u>
STEPS
<em>Step 1: </em>Round $68.28 to $70.00
<em>Step 2:</em> convert 25% to a decimal-------- .25
<em>Step 3:</em> multipy .25 x 70= 17.5
Let me know if you need any other help!!