1). Make your equation equal to 0
2). Then plug in your numbers to the quadratic equation
Answer:
add 21 to both sides to get everything on one side
x^2 - 10x + 21 = 0
do factorization, guess and check
(x - 7) (x -3) = 0
x =7, and x =3
Answer:
1. Her time in minutes is 720/s minutes
2. Given her time to be 20 minutes, her speed is 36 mph
Step-by-step explanation:
Mathematically,
Distance = speed * time
In this question, we want to calculate time;
So time = distance/speed
times = 12 miles/s mph = 12/s hours
Now we want our answer in minutes
Kindly recall that 60 minutes = 1 hour
So 12/s hours will be 12/s * 60 = 720/s minutes
2. Since she drives from home to the office in in 20 minutes, we want to calculate her speed in mph
From the time calculated above i.e 720/s
We can equate 20 = 720/s
20s = 720
s = 720/20
s = 36 mph
Answer:
The y-intercept of the line is 2
Step-by-step explanation:
You could try to find the slope of the line and then find the intercept with y axis by sloving b = y - ax
But here it seems easy enough once you see that the x values in the table increase by a factor of 8 and the y values in the table increase by a factor of 20.
(By the way, this is enough to give you the slope, because it is 8/20 ). But why bother?
Just extrapolate the table to the left, and you will find the y value where x = 0
x 0 8 16 24 32
y 2 22 44 64 84
So the y-intercept of the line is 2.
Extra:
The full equation of the line is:
y = 8/20x + 2