Answer:

Explanation:
sin = opposite divided by the hypotenuse
the opposite side of the angle that has a measure of 70 degrees is x and the hypotenuse is 12
so

we want to isolate the variable using inverse operations
to get rid of the 12 we multiply each side by 12

we're left with

now we let a calculator do the rest of the work
x = 11.27631145
our final step is to round to the nearest tenth
So we can conclude that x = 11.3