No.045 Tables and Direct Proportion
POINT
① Choose one pair of x and y values from the table and substitute them into y = ax to find a.
② Substitute x or y into the equation to find the missing values.
② Substitute x or y into the equation to find the missing values.
PROBLEM
Look at the table and answer the questions.
① Express the relationship between x and y as an equation.
② Fill in the missing numbers in the table.
| x | −2 | −1 | 0 | 1 | 2 | 5 | C |
|---|---|---|---|---|---|---|---|
| y | A | −2 | 0 | 2 | 4 | B | 24 |
Watch. Think. Try.
Try it yourself.
Find the proportional rule and complete each table. Then reveal the answer.
01
Look at the table. ① Express y in terms of x. ② Find A and B.
| x | −3 | −1 | 0 | 2 | 4 |
|---|---|---|---|---|---|
| y | A | −4 | 0 | 8 | B |
\(y = 4x, A = -12, B = 16\)
02
Look at the table. ① Express y in terms of x. ② Find A and B.
| x | −4 | −2 | 0 | 3 | A |
|---|---|---|---|---|---|
| y | 12 | 6 | 0 | −9 | −15 |
\(y = -3x, A = 5\)
03
Look at the table. ① Express y in terms of x. ② Find A and B.
| x | −6 | −2 | 0 | B | 8 |
|---|---|---|---|---|---|
| y | 3 | 1 | 0 | −2 | A |
\(y = -½x, A = -4, B = 4\)
04
Look at the table. ① Express y in terms of x. ② Find A and B.
| x | −5 | −2 | 0 | 3 | A |
|---|---|---|---|---|---|
| y | 10 | 4 | 0 | −6 | −8 |
\(y = -2x,\ A = 4\)
05
Look at the table. ① Express y in terms of x. ② Find A and B.
| x | −4 | −1 | 0 | 2 | B |
|---|---|---|---|---|---|
| y | −2 | −1/2 | 0 | 1 | 3 |
\(y = \frac{1}{2}x,\ B = 6\)