Step-by-step explanation:first, you need to figure out what side you’re looking for. Side AC is opposite of the angle you’re given. They also give you length of side AB which is 4. That is the hypotenuse (side directly across from right angle). So, you have the hypotenuse, and need the find the opposite side measure. Which option uses opposite and hypotenuse? That’s Sin. So, you would do: sin70 = ? / 4.
sin (of given angle)= opposite / hypotenuse.
Sin (70 degrees) = ? / 4
Then you solve for “?”
Type sin70 into your calculator, then multiply both sides by 4 to get “?” by itself. You should get 3.758770483, which rounds to 3.8
