The hypotenuse of a certain triangle is 5 units long and one leg is 3 units long. Find
the area of the triangle.

If the given 5 units and 10 units are both legs of the right triangle, then the answer should be 11.18 units.

For the number 7, begin by solving for k.
Remember your discriminant rules:
k is greater than 0, there are 2 real solutions
k is equal to 0, there is one real solution
k is less than 0, there are no real solutions

On number 8, solve for a, and then figure out the number of solutions using the rules above.

Hope this helps!