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.
Answer:
1/5 × 40 = 8
the person's speed is 8 miles per hour
Answer:
Step-by-step explanation:
A ratio is a comparison of two quantities and can be written in several forms including fractions. It is most commonly written in fraction form or a:b.
To write a ratio, we count the number of each quantity we are comparing or use the variable for that quantity. We write radius:circumference. Recall, the circumference of a circle can be found using 
or 
.
We write r: or r:.
We can also write in fraction form:
or
First list all the factors of 12;
1, 2, 3, 4, 6, 12
now let's see which ones are multiples of 3;
3, 6, 12
so all we have left are numbers 1, 2 and 4.
hope that helps, God bless!
