(6,-5) (7,-3) (8,-1) (9,1) is this a function?

What is the average diastolic blood pressure for adults

If the altitude is drawn to the hypotenuse of a right triangle, then the two triangles formed are similar to the original triangle and to each other. which set of triangles shows the similar triangles created by the altitude in the diagram?

Find the least common factor denominator for these two rational 7/x^2 and 7/5x