(08.02 MC) A pair of equations is shown below:

y = 2x − 1
y = 4x − 5

Part A: In your own words, explain how you can solve the pair of equations graphically. Write the slope and y-intercept for each equation that you will plot on the graph to solve the equations. (6 points)

Part B: What is the solution to the pair of equations? (4 points)

part A

y = 2x -1

the slope is 2/1 means it will be up 2 right 1 or down 2 left 1 the slope is positive

the y-int is -1

y = 4x -5

the slope is 4/1 means it will be up 4 right 1 or down 4 left 1 the slope is positive

the y-int is -5

part B  

the solution to this is (2,3)

Step-by-step explanation:

Part A:

y = 2x - 1

Slope = 2/1

Y intercept = -1

y = 4x -5

Slope = 4/1

Y intercept = -5

Part B:

x = 2    y = 3

Step-by-step explanation:

Part A: To solve the pair of equations graphically, we need to plot the 2 lines on a graph, and look at where they intercept. Then we draw a vertical line from the intersection to the x axis and we know what x is equal to. Laslty, we draw another line (horizontal) from the intersetcion to the y axis and we know what y is equal to.

Equation of a line: y = mx + c

where mx is the slope and c is the y intercept

y = 2x - 1

Slope = 2/1 -- 2 divided by 1 because it goes 2 squares up and 1 to the right

y intercept = -1

y = 4x - 5

Slope = 4/1

y intercept = -5

Part B:

Solving for x:

Since we know that y = 2x - 1 but also 4x - 5, then:

2x - 1 = 4x - 5

2x + 4 = 4x

4 = 2x

x = 2

Solving for y:

Since we know that x = 2, we just have to replace it in one of the two equations, let's say y = 2x - 1. This would give us:

y = 2 x 2 - 1

y = 4 - 1

y = 3