5(xy) simplified is 5x+5y. This does not equal x3+y2. :)
Using Pythagoras:-
x^2 = 6^2 + (sqrt18)^2
= 36 + 18 = 54
x = sqrt54 = 3 sqrt6
Answer:
1) From the measure of 40°, you can write:
tan(40°) = 100/x, where x is the base from the building to the tower
⇒x=100/tan(40°) = 119,18 m
2) From the measure of 30°, you can write
tan(30°) = y / 119,18, where y is the height from the roof of Jill's building to the top of the tower.
Then, y = tan(30°) * 119,18 = 68,81 m
3) The height of Jill's building is 100 - 68,81 = 31,19 m
According to HL theorem if one leg and hypotenuse of one right triangle are equal to one leg and hypotenuse of other right triangle, then the triangles are congruent.
By using this theorem we can set up the system of equations as follows:
x=y+1 ...(1)
2x+3= 3y + 3 ..(2)
By using equation (1) next step is to plug in y+1 for x in equation (2). So,
2 ( y + 1) + 3 = 3y + 3
2y + 2 + 3 = 3y + 3 By using distribution property.
2y + 5 = 3y + 3
2y + 5 - 5 = 3y + 3 - 5 Subtract 5 from each side.
2y = 3y - 2
2y - 3y = -2 Subtract 3y from each sides.
-y = -2
So, y=2
Next step is to plug in y=2 in equation (1) to get the value of x. Hence,
x= 2+1
=3
So, x=3 and y=2 make these triangles congruent.
So, the correct choice is 3. x = 3, y = 2.
You can solve this problem by using the Gauss method. The Gauss method is a method where you can add the first and last numbers together, and then multiply by how many times that appears. Here, the sum of the first and last number is -11. In this sequence, it would appear ten times (since there are ten terms and the terms are used twice in every eleven). -11 * 5 is -55, so that means the answer to this question is -55.