Answer:
<u><em>For x - y = 2</em></u>
You need to find x or y in one of the equations and then substitute that into the other.
So we have;
x-y=2
4x-3y=11
We will take the first equation and find x;
x-y=2
add y to both sides;
x-y+y=2+y
x=2+y
Now we take that answer and substitute it forx in the other equation;
4(2+y)-3y=11
8+4y-3y=11
8+y=11
y=3
Now we have what y equals, so we use it in the first equation to find x;
x-3=2
x=5
So we have;
x=5; y=3
Hope you understand!
=)
<u><em>And for 4x – 3y = 11</em></u>
Multiply the first equation by 2 and the second by 3 so that there are the same number of y's in each:
8x - 6y = 22 ...(3)
30x + 6y = -3 ...(4)
Now add (3) and (4) term by term:
38x + 0 = 19
or
38x = 19
or x = 1/2
Put this back into equation (1)
4*(1/2) - 3y = 11
or
2 - 3y = 11
Subtract 2 from both sides:
-3y = 9
Divide both sides by -3
y = -3
Answer:
4
Step-by-step explanation:
The x coordinate of the vertex will be the average of the two zeros, here -3 and 5, so x=(-3+5)/2 = 1, f(1)=(1+3)(1-5) = -16.
Answer: (1, -16)
Let's do it some other ways. How about completing the square to turn f in to vertex form?
f(x) = (x+3)(x-5) = x² - 2x - 15 = (x² - 2x + 1) - 1 - 15 = (x-1)² - 16
and now we can read off (1, -16) as the vertex.
The other method is the vertex is x= - b/2a = - (-2)/2(1) = 1.
Three methods, same answer. Good.
Answer:
31 years to triple the investment
Step-by-step explanation:
Initial investment = 300
Triple amount that is final amount = 300*3= 900
rate of interest = 3.5 % = 0.035
we need to find out number of years (t)
for compounded continuously we use formula
A is the final amount
P is the initial amount
r is the rate of interest
t is the number of years
Divide both sides by 300
take 'ln' on both sides
ln(3) = 0.035t ln(e)
ln(e)= 1
t= 31.3889
Round to nearest whole number
t= 31 years
$500 x 0.85 = 425
$425 x 0.85 = 361.25
$361.25 x 0.85 = 307.10
$307.1 x 0.85 = 261
$261 x 0.85 = 221.85
