# Formulas, substitution and equations I

## Interactive practice questions

The area of a rhombus is given by the formula $A=\frac{1}{2}xy$A=12xy, where $x$x and $y$y are the lengths of the diagonals.

If the diagonals of a rhombus have lengths of $2$2 cm and $4$4 cm, find the area of the rhombus.

Easy
Less than a minute

The value of a variable $T$T is defined by the formula $T=a+\left(n-1\right)d$T=a+(n1)d.

Given that $a=6$a=6, $n=5$n=5 and $d=8$d=8, find the value of $T$T.

Sally bought a television series online. The television series was $7.2$7.2 gigabytes large and took $2$2 hours to download.

Conversion from Fahrenheit to Celsius is defined by the formula $C=\frac{5}{9}\left(F-32\right)$C=59(F32).

The temperature inside a freezer is $86^\circ$86°$F$F. What is this temperature in Celsius?