Middle Years
11.01 Directly proportional functions
Interactive practice questions
Consider the values in each table. Which of them could represent a directly proportional relationship between $x$x and $y$y?
| $x$x | $1$1 | $3$3 | $5$5 | $7$7 |
|---|---|---|---|---|
| $y$y | $20$20 | $16$16 | $12$12 | $8$8 |
A
| $x$x | $1$1 | $5$5 | $6$6 | $20$20 |
|---|---|---|---|---|
| $y$y | $16$16 | $12$12 | $8$8 | $4$4 |
B
| $x$x | $1$1 | $2$2 | $3$3 | $4$4 |
|---|---|---|---|---|
| $y$y | $2$2 | $8$8 | $18$18 | $32$32 |
C
| $x$x | $1$1 | $2$2 | $3$3 | $4$4 |
|---|---|---|---|---|
| $y$y | $2$2 | $4$4 | $6$6 | $8$8 |
D
Easy
< 1min
Which two of the following graphs indicate that $y$y is directly proportional to $x$x?
Easy
< 1min
$a$a is directly proportional to $b$b and $a=54$a=54 when $b=9$b=9.
Easy
3min
Consider the equation $y=6x$y=6x.
Easy
1min
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