13. five plus <em>y</em> equal to negative two. y = -7
14. eight plus <em>h</em> equal to twelve. h = 4
15. negative thirteen plus four equal <em>n</em>. n = -9
Answer:
x = 53
y = 30
Step-by-step explanation:
Step(I):-
Given equations are
x -2y =-7 ...(I)
5x-9y =-5 ..(ii)
The matrix form AX = B
![\left[\begin{array}{ccc}1&-2\\ 5 & -9\\\end{array}\right] \left[\begin{array}{ccc}x\\y\\\end{array}\right] = \left[\begin{array}{ccc}-7\\-5\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%26-2%5C%5C%205%20%20%26%20-9%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dx%5C%5Cy%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-7%5C%5C-5%5C%5C%5Cend%7Barray%7D%5Cright%5D)
The determinant

By using Cramer's Rule
Δ₁ =
The determinant is Δ₁ = -9 X -7 - (10 ) = 53
x = Δ₁ / Δ
x = 53
The determinant
Δ₂ =
Δ₂ = -5 +35
y = Δ₂/Δ = 30
There is a little-known theorem to solve this problem.
The theorem says that
In a triangle, the angle bisector cuts the opposite side into two segments in the ratio of the respective sides lengths.
See the attached triangles for cases 1 and 2. Let x be the length of the third side.
Case 1:
Segment 5cm is adjacent to the 7.6cm side, then
x/7.6=3/5 => x=7.6*3/5=
4.56 cm
Case 2:
Segment 3cm is adjacent to the 7.6 cm side, then
x/7.6=5/3 => x=7.6*5/3=
12.67 cmThe theorem can be proved by considering the sine rule on the adjacent triangles ADC and BDC with the common side CD and equal angles ACD and DCB.
Answer:
1. Answer: F = P123,514.09
Step-by-step explanation:
1. Peter started to deposit P5,000 quarterly in a fund that pays 1% compounded quarterly. How much will be in
the fund after 6 years?
1. Answer: F = P123,514.09