Answer:
After 23 years , the capital will get three times as big
Step-by-step explanation:
Firstly, let us write the compound interest formula
P = I( 1 + r)^n
Since we are considering a capital rise of 3 times
If I, the initial value is x, the P
value later will be 3x
Interest rate is 5/100 = 0.05
so we need the value of t
This will be;
3x = x(1 + 0.05)^t
3= 1.05^t
ln 3 = t ln 1.05
t = ln 3/ln 1.05
t = 23 years
Answer:
12.3693
Step-by-step explanation:
use distance formula
You want to eliminate one of the terms (x or y) in one of the equations so you can solve for the other variable. You have to multiply by the opposite number of the coefficient to be able to eliminate the term in the other equation. If the x coefficient is 2, then you have to multiply the entire other equation by -2. If the y coefficient is -5, then you have to multiply the entire other equation by 5.
10)
-4x + 9y= 9
x - 3y= -6
STEP 1:
multiply the bottom equation by 4
4(x- 3y)= 4(-6)
4x - 12y= -24
STEP 2:
add the top equation and the equation from step 2
-4x + 9y= 9
4x - 12y= -24
the x term cancels out
-3y= 15
divide both sides by -3
y= -5
STEP 2:
substitute the y value in either original equation to solve for x
x - 3y= -6
x - 3(-5)= -6
x + 15= -6
subtract 15 from both sides
x= -21
ANSWER: x= -21; y= -5
____________________
12)
-7x + y= -19
-2x + 3y= -19
STEP 1:
multiply the top equation by -3 to eliminate the y term and to solve for x
-3(-7x + y)= -3(-19)
21x - 3y= 57
STEP 2:
add the bottom equation and the equation from step 2 to solve for x
-2x + 3y= -19
21x - 3y= 57
the y term cancels out
19x= 38
divide both sides by 19
x= 2
STEP 3:
substitute the x value in step 2 to solve for y; you can use either original equation
-7x + y= -19
-7(2) + y= -19
-14 + y= -19
add 14 to both sides
y= -5
ANSWER: x= 2; y=-5
Hope this helps! :)
When x is -1 Y will equal -1
No.
Tom forgot about the area of the top/roof, the floor and roof are different dimensions/areas, making his method incomplete.
He needs to find area of Roof, Floor then times height.