Problem #1
Is this correct or wrong?
Find the slope of the line passing through the points(-1, -1)and(-1, 2). Write the equation of the line.
For this one I KEEP GETTING
Y= - (3)/(2)x-2.5
Problem #2
Find the y-intecept and slope of
7x+9y=72
My answer:
Slope is: - (9)/(8)
y-intercept: (0,8)
The equation of a straight line is given by
(y2-y1)/(X2-x1)
In your example
Y2=2, y1=-1
x2=-1, x1=-1
substitute and find the slope
In the second part the general equation of a straight line is given by
y=mx+c where m=slope and c=intercept.
you need to compare the equation given with the general equation, but to do that they need to be in the same form
i.e y=mx+c
but 7x+9y=72 is not in this form
To get you started subtract 7x from each side:
9y=72-7x
but this is still not in the correct form so you still need to rearrange it.
Problem #1:
To find the slope of the line passing through the points (-1, -1) and (-1, 2), we can use the slope formula. The formula for the slope of a line passing through two points (x1, y1) and (x2, y2) is (y2 - y1) / (x2 - x1).
In this case, we have (x1, y1) = (-1, -1) and (x2, y2) = (-1, 2).
Now substitute the values into the slope formula:
slope = (2 - (-1)) / (-1 - (-1))
Simplifying:
slope = 3 / 0
The slope formula gives us a division by zero, which is undefined. This means that the line passing through the points (-1, -1) and (-1, 2) does not have a defined slope.
Regarding your equation, Y = - (3)/(2)x - 2.5, it seems to have a slope and y-intercept, but it does not match the coordinates you provided. It is always a good idea to double-check your calculations and ensure that you are using the correct formula.
Problem #2:
To find the y-intercept and slope of the equation 7x + 9y = 72, we need to rearrange the equation in the form y = mx + c, where m is the slope and c is the y-intercept.
Start by subtracting 7x from both sides of the equation:
9y = 72 - 7x
Next, divide both sides of the equation by 9 to isolate y:
y = (72 - 7x) / 9
Now you have the equation in the form y = mx + c. By comparing this equation with the general form, we can identify the slope and y-intercept.
The slope (m) is the coefficient of x, so in this case, the slope is -7/9.
The y-intercept (c) is the value when x = 0. Substituting x = 0 into the equation, we get:
y = (72 - 7(0)) / 9
y = 72 / 9
y = 8
Therefore, the y-intercept is (0, 8).
It looks like your answers for the slope and y-intercept are correct:
Slope = -7/9
Y-intercept = (0, 8).