Hey there!
4/5 = x/9
CROSS-MULTIPLY the fractions
4 * 9 = x * 5
4 * 9 = 5 * x
SIMPLIFY IT!
36 = 5x
5x = 36
DIVIDE 5 to BOTH SIDES
5x/5 = 36/5
SIMPLIFY IT!
x = 36/5
Therefore, the answer should be:
x = 36/5
Good luck on your assignment & enjoy your day!
~Amphitrite1040:)