SOLUTION: Find the intersection of the following pairs of lines. f(x)=3x+8, g(x)=6x+1 He does not want the composition answer. Please help me.

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Question 214304: Find the intersection of the following pairs of lines.
f(x)=3x+8, g(x)=6x+1
He does not want the composition answer. Please help me.
Found 2 solutions by scott8148, drj:
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the functions are equal at the point of intersection

3x + 8 = 6x + 1

7 = 3x ___ 7/3 = x

substitute to find the value of the functions ___ 3(7/3) + 8 = 15

intersection is (7/3 , 15)

Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
Find the intersection of the following pairs of lines.

f(x)=3x+8, g(x)=6x+1

He does not want the composition answer. Please help me.

Step 1. We can write the above equations as

y=3x%2B8

y=6x%2B1

Step 2. Since these two lines intersect they save the same y or

3x%2B8=6x%2B1

Step 3 Add -3x-1 from both sides of equation to get only x-terms on the right side and only numbers on the left side.

3x%2B8%2B%28-3%29x-1=6x%2B1%2B%28-3%29x-1

7=3x

Step 4. Divide by 3 to both sides of the equations.

7%2F3=3x%2F3

7%2F3=x or x=7%2F3

Step 5. Now substitute x=7/3 into above equations and it should yield the same y.

y=3x%2B8=3%2A%287%2F3%29%2B8=7%2B8=15

y=6x%2B1=6%2A%287%2F3%29%2B1=14%2B1=15

and y=15 for both equations

Step 6. ANSWER: The intersection point is (7/3, 15)

A graph of the lines is shown below and note the intersection point.

graph%28400%2C400%2C+-5%2C+5%2C+-25%2C+25%2C+3x%2B8%2C+6x%2B1%29

I hope the above steps were helpful.

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

And good luck in your studies!

Respectfully,
Dr J