Answer:
x= 2√ 7
Explanation:
We can solve it with applying the sin of 30°
Sin 30° = opposite leg / hypotenuse
Sin 30° = √ 7 / x
Being x unknown.
Now, being 30° a notable angle, we know that its sin is 1/2.
Sin 30° = 1/2
Replacing,
Sin 30° = √ 7 / x. (we clear x)
1/2 = √ 7 / x
x/2 = √ 7
x= 2√ 7