Answer:
x = 21
Step-by-step explanation:
Using ratios:
75 : 25 = x : 7
75/25 = x/7
3 = x/7
21 = x
Using Pythagoras' Theorem a² + b² = c², where a and b are the legs and c is the hypotenuse of a right triangle:
[tex]72^2+x^2=75^2[/tex]
[tex]\implies x^2=75^2-72^2[/tex]
[tex]\implies x=\sqrt{75^2-72^2}[/tex]
[tex]\implies x=21[/tex]
