25.4k views
0 votes
Where do y=2x+4 and y=2.50x+2 intersect

User Olchick
by
7.1k points

2 Answers

3 votes
The point of intersection is (-1,3)
Where do y=2x+4 and y=2.50x+2 intersect-example-1
User JediBurrell
by
8.3k points
3 votes

Answer:

(4, 12)

Explanation:

When the two lines intersect on a graph, it is when you can put the same value for "x" into both equations, and the same value for "y" into both equations.

Because they both equal "y", and y = y, you can equate the expressions together.

y = y

2x + 4 = 2.50x + 2

Now the goal is to move all the numbers with "x" to the left. Move the the numbers to the right side. (This is called isolating "x" because it will be alone).

2x + 4 - 4 = 2.50x + 2 - 4 Subtract 4 from both sides

2x = 2.50x - 2

2x - 2.50x = 2.50x - 2.50x - 2 Subtract 2.50x from both sides

-0.50x = -2

-0.50x/-0.50 = -2/-0.50 Divide both sides by -0.50

x = 4 Found "x" coordinate

Choose one of the original equations. Change "x" to 4 (called substitution).

y = 2x + 4

y = 2(4) + 4 Multiply first

y = 8 + 4 Add

y = 12 Found "y" coordinate

Now write the coordinates like an ordered pair (x, y).

The lines intersect at (4, 12).

User Egor Stepanov
by
7.1k points