I need help on number 3 please

Answer:
[tex]\large\boxed{x=10}\\\\\boxed{40^o,\ 50^o,\ 90^o}[/tex]
Step-by-step explanation:
We have the right triangle. The sum of the angles measured in the right triangle is 90 °. Therefore we have the equation:
[tex]4x+(6x-10)=90[/tex]
[tex]4x+6x-10=90[/tex] add 10 to both sides
[tex]10x=100[/tex] divide both sides by 10
[tex]x=10[/tex]
The measure of angles:
Put the value of x to the eqpressions:
[tex]6x-10\to6(10)-10=60-10=50\\\\4x\to4(10)=40[/tex]