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Question 78779This question is from textbook Pre-Algebra
: Use a graph to solve each system of equations.
15. y=x+5
y=2x+6
And then it gives me a graph to graph it!!
HEPL PLEASE I HAVE A TEST TOMORROW AND I KEEP ON GETTING F AND I CAN"T FAIL MATH CUZ I"M GOING TO GET IN BIG TROOUBLE!!! HELP PLEASE!!
This question is from textbook Pre-Algebra
Answer by mathdoc314(58)   (Show Source):
You can put this solution on YOUR website!
Well do you know how to graph?
You start with two number lines sorta like this
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4
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3
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2
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1
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-1--0--1--2--3--4--
Then you graph the two lines. y=x+5 has slope=1 and y-intercept is 5
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6 /
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5
/|
/ 4
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....
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-1--0--1--2--3--4--
but you have to do that on paper because it is hard to type. The other
one y = 2x + 6 it has slope=2 (steeper) and y-intercept is 6 so
7 /
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6 /
/| /
/ 5
/ /|
/ 4
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....
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-1--0--1--2--3--4--
From this crude graph it appears to me that maybe they cross at
x=-1 and y=4. Is this true? You can verify it:
x=-1 -> plug into y = x + 5 ->> y is -1+5 which is 4
(x = -1, y = 4)
the point (-1, 4) is on the first line!
x=-1 -> plug into y=2x + 6 -->> y is -2+6 which is also 4
(x = -1, y = 4)
the point (-1,4) is on the second line!
So (-1, 4) is the point where they intersect.
Does this make sense? I typed a lot so you would be able to
understand it all. I am not sure which part of graphing two lines
and spotting the intersection you found to be tricky.
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