write the slop - intercept form of the equation wiht the given slope and intercept
slope:2/5 x-int=4.5
i knwo how to do it with y-int
but how doyou do it with x- int?
y = mx + b, and you're right, we do not know the y-intercept here.
so, y = (2/5)x + b.
They tell us the X-intercept is 4.5. How does this help us? The x-intercept is where it crosses the x-axis. At that point, y = 0. So, the line crosses the point (4.5,0).
So, now we substitute in 0 for y and 4.5 for x:
0 = (2/5)(4.5) + b.
We can solve for b, and we get
b= -9/5.
So, we now have our y-intercept, and use y = mx + b.
Does this make sense??
thank you =D
you're welcome!
To write the slope-intercept form of an equation using a given slope and x-intercept, we can use the following steps:
1. Start with the general slope-intercept form of an equation: y = mx + b, where m represents the slope and b represents the y-intercept.
2. Substitute the given values into the equation:
- The slope, m, is given as 2/5.
- The x-intercept is given as 4.5.
3. To convert the x-intercept to the y-intercept, recall that the x-intercept is the point where the graph intersects the x-axis, which means the y-coordinate at that point is zero. Write the x-intercept as an ordered pair (x, y), where x is the x-intercept and y is the y-intercept (which is zero in this case).
In this example, the x-intercept is 4.5, so the ordered pair is (4.5, 0).
4. Substitute the values into the equation:
- The slope, m, remains the same: y = (2/5)x + b.
- The x-coordinate, x, is 4.5: y = (2/5)(4.5) + b.
5. Simplify the equation: y = (9/5) + b.
6. To find the y-intercept, use the ordered pair notation (y, x). From the equation, we can determine that the y-intercept is (9/5, 0).
- Since the y-coordinate is zero, the y-intercept is (0, 9/5), which is the slope-intercept form.
7. Therefore, the slope-intercept form of the equation, with the given slope and x-intercept, is: y = (2/5)x + 9/5.