Answer:
b. y-y1 = m(x-x1)
Step-by-step explanation:
It's a matter of definition. There are perhaps a dozen useful forms of equations for a line. Each has its own name (and use). Here are some of them.
- slope-intercept form: y = mx + b
- point-slope form: y -y1 = m(x -x1)
- two-point form: y = (y2-y1)/(x2-x1)(x -x1) +y1
- intercept form: x/a +y/b = 1
- standard form: ax +by = c
- general form: ax +by +c = 0
Adding y1 to the point-slope form puts it in an alternate form that is useful for getting to slope-intercept form faster: y = m(x -x1) +y1. I use this when asked to write the equation of a line with given slope through a point, with the result in slope-intercept form.
-8 * -4 = 32
Just multiply both numbers and negatives cancel
Answer:
What is this I have not understand
2x -3y = 13
4x -y = -9
Multiply the second equation by -3 to make the coefficient of Y opposite the first equation.
4x -y = -9 x -3 = -12x + 3y = 27
Now add this to the first equation:
2x -12x = -10x
-3y +3y = 0
13 +27 = 40
Now you have :
-10x = 40
Divide each side by -10:
x = 40 / -10
x = -4
Now you have a value for x, replace that into the first equation and solve for y:
2(-4) - 3y = 13
-8 - 3y = 13
Add 8 to both sides:
-3y = 21
Divide both sides by -3:
y = 21/-3
y = -7
Now you have X = -4 and y = -7
(-4,-7)
Answer:
option C
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Step-by-step explanation:
we have

solve for x

Subtract
both sides


Divide by
both sides
--------> is equivalent to 
The solution is the interval--------> [9,∞)
All real numbers greater than or equal to 
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