A coordinate grid is very handy when it comes to drawing geometric shapes such as triangles. Let's create an example triangle ABC with the locations
A = (2,3)
B = (9,5)
C = (4,-10)
Plot those points and connect the dots. That forms triangle ABC. We can translate triangle ABC to any other position we want. Let's say we want to shift it 2 units to the left. That means we subtract 2 from each x coordinate while keeping the y coordinates the same. Therefore
A' = (0, 3)
B' = (7, 5)
C' = (2,-10)
Plot triangle A'B'C' and you should see that this is a shifted copy of triangle ABC.
The rotation rules are a bit more complicated, and it depends where you place the center of rotation; however, it is possible to use coordinate math like done above.
Luckily the reflection rules over the x or y axis are fairly simple. If we reflect over the x axis, then we flip the sign of the y coordinate. Or if we wanted to reflect over the y axis, we flip the sign of the x coordinate.
Example: A' = (0,3) reflects over the x axis to get A'' = (0, -3)
Answer:
$3,000 was invested in the account that gained 13%
$17,500 was invested in the account that lost 10%
Step-by-step explanation:
Let the amount in both accounts be x and y
x for the first and y for the second
Adding both is 20,500
x + y = 20,500 •••••(i)
First account earned 13% profit
= 13/100 * x = 0.13x
Second account, a loss of 10%
= -10/100 * y = -0.1y
Total loss of -1,360
This is;
-0.1y + 0.13x = -1,360 •••••••(ii)
From i, x = 20,500-y
Insert this into ii
-0.1y + 0.13(20,500-y) = -1,360
-0.1y + 2665 -0.13y = -1360
-0.23y = -1360-2665
-0.23y = -4025
y = -4025/-0.23
y = 17,500
To get x, we have
x = 20,500 -y
x = 20,500- 17,500
x = 3,000
The following equations are solved in terms of x:
a) 2x - 3 = y
2x = y + 3
x = (1/2)y + 3/2
b) 2 + 2x - 1 = 4y
2x - 1 = 4y
2x = 4y + 1
x = 2y + 1/2
c) 2A + 4x + 3B = 10
4x = 10 - 2A - 3B
x = 5/2 - (1/2)A - (3/4)B
