Question

Which expression has a value of 15 when n = 7?

Answer 1

Answer:

$19-\frac{28}{n}$ is the expression with the value of 15 when n = 7

Step-by-step explanation:

To find the expression whose value is 15, substitute the value of n = 7 in each given expression.

Expression 1:

$43-5n$

Substitute the value of n & simplify,

$43-5(7)$

$43-35=8$

Since the value of the expression is 8 which is not equal 15.

Hence expression $43-5n$ does not have value of 15 when n = 7.

Expression 2:

$3n-5$

Substituting the value of n & simplify,

$3(7)-5$

$21-5=16$

Since the value of the expression is 16 which is not equal 15.

Hence expression $3n-5$ does not have value of 15 when n = 7.

Expression 3:

$6n-28$

Substituting the value of n & simplify,

$6(7)-28$

$42-28=14$

Since the value of the expression is 14 which is not equal 15.

Hence expression $6n-28$ does not have value of 15 when n = 7.

Expression 4:

$19-\frac{28}{n}$

Substituting the value of n & simplify,

$19-\frac{28}{7}$

$19-4=15$

Since the value of the expression is 15 which is equal 15.

Hence expression $19-\frac{28}{n}$ has the value of 15 when n = 7.