Look at the picture.
To find the area of triangle DBC we need to find its base, x, and its height, h.
Triangle ABC is a right triangle, so using the Pythagorean theorem we can find x.

Now look at triangles ABC and DBH. They both are right triangles and have the same angle α. That means they're similar and their corresponding sides are proportional. The ratio of the side opposite to angle α to the hypotenuse is the same in both triangles - so the ratio of h to 1 is the same as the ratio of 3 to 5.

The base x is 4, the height h is 3/5. Calculate the area:

The area of triangle DBC is 6/5.
Answer:
A. 5
Step-by-step explanation:
12 times 5 is 60 plus 10 is 70. 70 < 75
YOUR ANSWER IS 9
HOPE IT HELPS:)
We are given the functions:
f(x) = 4 x – 5 --->
1
g(x) = 3 x + 7 --->
2
To find for the value of f(x) + g(x), all we have to do is
to add equations 1 and 2:
f(x) + g(x) = 4 x – 5 + 3 x + 7
f(x) + g(x) = 7 x + 2 = y
In this case, for any real number value assign to x, we get
a real number value of y. This is because the function is linear.
Therefore the domain of the function is all real numbers.
Answer:
52º, 128º
Step-by-step explanation:
8. Because ∠6 is an opposite angle to ∠5, ∠6=∠5=52º;
9. Because line a//line b, ∠6=∠4=52º, so ∠7=180º–52º=128º