think wrote:Solve 5x^2=10
Divide through by the 5. Then take the square root of either side, and simplify.
think wrote:find the x-intercepts of f(x)=5x^2-10?
Plug "zero" in for "y" (that is, for f(x)), and solve the resulting quadratic equation.
Note: I think the "point" of this exercise is that you notice the connection between the zeroes of a function f(x) and the solution of the related equation f(x) = 0, since "f(x) = 5x
^{2} - 10 = 0" means the same thing as "5x
^{2} = 10".