The triangles ABC and EDF are congruent, meaning they have the same side lengths and angles measures.
The measure of DF, as both triangles are congruent, is equal to the measure of BC.
We can calculate the length of BC using the distance formula:
![\begin{gathered} D=\sqrt[]{(x_c-x_b)^2+(y_c-y_b_{})^2} \\ D=\sqrt[]{(2-2)^2+(-1-4)^2} \\ D=\sqrt[]{0^2+(-5)^2} \\ D=\sqrt[]{(-5)^2} \\ D=|-5| \\ D=5 \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20D%3D%5Csqrt%5B%5D%7B%28x_c-x_b%29%5E2%2B%28y_c-y_b_%7B%7D%29%5E2%7D%20%5C%5C%20D%3D%5Csqrt%5B%5D%7B%282-2%29%5E2%2B%28-1-4%29%5E2%7D%20%5C%5C%20D%3D%5Csqrt%5B%5D%7B0%5E2%2B%28-5%29%5E2%7D%20%5C%5C%20D%3D%5Csqrt%5B%5D%7B%28-5%29%5E2%7D%20%5C%5C%20D%3D%7C-5%7C%20%5C%5C%20D%3D5%20%5Cend%7Bgathered%7D)
As BC is congruent with DF and BC=5, the length of DF is 5 units.
X= 2 and y=-2 check by multiplying
Answer:

Step-by-step explanation:
We want to write the trignometric expression:

As an algebraic equation.
First, we can focus on the inner expression. Let θ equal the expression:

Take the secant of both sides:

Since secant is the ratio of the hypotenuse side to the adjacent side, this means that the opposite side is:

By substitutition:

Using an double-angle identity:

We know that the opposite side is √(u² -100), the adjacent side is 10, and the hypotenuse is u. Therefore:

Simplify. Therefore:

You could put the ‘+6’ at the start of the equation so it would read as +6(x2+8x) and then expand the bracket as you normally would so you would get x2x6 which would get you 12x and then 6x8x which would get you 48x and then you could group both numbers together as they’re like terms and your final answer would be 60x