ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos


Algebra II Videos 107 videos

ACT Math 3.4 Pre-Algebra
371 Views

ACT Math Pre-Algebra: Drill 3, Problem 4. Find the solution to this equation.

GED Math 5.2 Rational Numbers
249 Views

GED Math 5.2 Rational Numbers. Solve the equation.

SAT Math 6.4 Algebra and Functions
486 Views

SAT Math 6.4 Algebra and Functions

See All

SAT Math 1.2 Algebra and Functions 359 Views


Share It!


Description:

SAT Math: Algebra and Functions Drill 1, Problem 2. Based on the data in the table, what is the maximum heart rate for the average 22-year-old?

Language:
English Language

Transcript

00:02

And we're getting math-y with it...

00:04

The table below gives the average maximum heart rate,

00:07

by age, for a person exercising at full effort.

00:11

Based on the data in the table,

00:13

what is the maximum heart rate for the average 22-year-old?

00:17

And here are your possible answers...

00:21

If we look at the data, as age increases by 5, average max heart rate decreases by 5.

00:28

Since age acts as our independent variable and average max

00:32

heart rate acts as our dependent variable,

00:38

we can calculate the change in average heart rate over age as the slope of our equation.

00:44

Which gives us negative 1.

00:46

The point slope form of a linear equation is y minus y1 equals slope times x minus x1.

00:54

h is y in this situation because it's the dependent variable, and a is x in this situation

01:01

because it's the independent variable.

01:04

We can take any x1 and y1 point to plug into the point-slope form of the equation...so

01:10

let's just take the points 20, 200.

01:13

We get h - 200 = -1(a - 20).

01:18

H minus 200 equals negative a plus 20.

01:22

Adding 200 to both sides of the equation... we have h equals 220 minus a.

01:27

We're looking for h given that a equals 22 years old.. so we get that h equals 198.

01:34

Answer's E.

Related Videos

SAT Math 9.4 Algebra and Functions
1300 Views

SAT Math 9.4 Algebra and Functions

SAT Math 2.1 Geometry and Measurement
2779 Views

SAT Math 2.1 Geometry and Measurement. What is the measure of angle z in terms of x and y?

SAT Math 9.2 Algebra and Functions
377 Views

SAT Math 9.2 Algebra and Functions

SAT Math: Identifying an Equation for the Average of Two Percentages
23 Views

In 2014, the unemployment rate of one county in California was 7%. In another county, the unemployment rate was 11%. Which of the following express...

SAT Math: Which Equation Represents Profit?
13 Views

Angela is making cookies for a bake sale. She expects each batch of her cookies to sell for $40. It costs her $10 to make one batch of cookies, and...