5c=y. This is the equation represented in the statement.
Ooh ok these are fun. So these triangles are similar, meaning they are in proportion. In triangle LMN, line LM is 21. To find the corresponding line on the other triangle, we need to find the corresponding letters in the names. Because L and M are the first two letters, we need to use the first two letter s in the other name, so FG. Line FG is 9, so our first proportion is 9/21
If we set the equation equal to 0, we can factor it to find its roots:
x² + 4x + 4 = 0
(x + 2)(x + 2) = 0
x = -2
This graph has one root, a double root, at -2. This means that a single point, which must be the vertex of the parabola, touches the x-axis at (-2, 0)
