(x^2+5)=7 and (x^2+5)k=21, what is the value of k?

What is the value of x in the diagram below?

30 pts, will mark brainliestwhat is the period of the sinusoidal function? (picture 1)what is the minimum of the sinusoidal function? (picture2)what is the maximum of the sinusoidal function? (picture 3)

Find the equation of a line whose slope is 2/5 and y- intercept is 2.write your answer in the form 1) ax+by+c=02) x/a+y/b=1