 Substitution resulting in an equation

Interactive practice questions

The area of a rectangle, $A$A, is given by the formula $A=L\times W$A=L×W, where $L$L is the length and $W$W is the width.

If the length of a rectangle is $15$15 cm, select the expression that gives the area of the rectangle in terms of the width.

$A=\frac{15}{W}$A=15W

A

$A=\frac{15}{L}$A=15L

B

$A=15L$A=15L

C

$A=15W$A=15W

D

$W=15A$W=15A

E

$A=15+W$A=15+W

F

$A=\frac{15}{W}$A=15W

A

$A=\frac{15}{L}$A=15L

B

$A=15L$A=15L

C

$A=15W$A=15W

D

$W=15A$W=15A

E

$A=15+W$A=15+W

F
Easy
Less than a minute

In physics, Newton's second law states that $F=ma$F=ma, where $F$F is the force of an object (measured in Newtons, N), $m$m is the mass of the object (in kilograms, kg) and $a$a is the acceleration of that object (measured in m/s2).

An object experiences an acceleration of $10$10 m/s2. Express the force on the object in terms of its mass.

The perimeter, $P$P, of a triangle with sides of lengths $x$x, $y$y and $z$z is given by the formula $P=x+y+z$P=x+y+z.

A triangle has two known side lengths, $x=5$x=5 cm and $y=8$y=8 cm. Express the perimeter of the triangle in terms of the unknown side length $z$z.

The perimeter, $P$P, of a rectangle is given by the formula $P=2\left(L+W\right)$P=2(L+W), where $L$L is the length and $W$W is the width.

If the length of a rectangle is $25$25 cm, select all expressions that give the perimeter of the rectangle in terms of the width.

Outcomes

9D.NA2.08

Rearrange formulas involving variables in the first degree, with and without substitution