21. randy owns a computer store. in 1990, he sold 150 monitors. in 2000, he sold 900
monitors. let x represent the number of years since 1990. write a linear equation, in
slope-intercept form, that represents this data.

Step-by-step explanation:

Let represent the number of monitors sold.

Given:

is the number of years since 1990.

So, for the year 1990, .

For the year 2000, 10 years passed. So, .

Now, monitors sold in 1990 are 150. So, at

Monitors sold in 2000 are 900. So, at

Thus, the two points are and .

The slope of a line with points and  is given as:

Slope,

For the points and , the slope is given as:

Slope,

Now, the y-intercept is the point where . So, the point has value as 0.

So, the y-intercept is 150.

Equation of a line in slope-intercept form is given as:

Where, is the slope and is the y intercept.

Here, and .

Therefore, the equation that represents the above data is given as:

3

step-by-step explanation:

in standard form:

a= dictionaries

b= maps

you have to buy 3 dictionaries, so put a 3 next to the a (dictionaries) so that you can multiply them by each other.

a3+b= 60 (the amount of money you have)

we already know the cost of a=15 so replace a with $15

($15 x 3)+b=60

multiply 15 and 3 to get $45 and replace it with $45

45+b=60

and then replace b with 15 to get the total:

45+15=60

that means you have $15 left after buying 3 dictionaries.

15 divided by the cost of a map ($5) equals 3.

so you can buy 3 maps.

sorry if it was confusing!