Answer:
Step-by-step explanation:
3x2 - y2 = 9.........(1)
x2 + 2y2 = 38......(2)
Let x^2 = a and y^2 = b
:- the two equations becomes
3a - b = 9..........(3)
a + 2b = 38.......(4)
Multiplying (4) by 3
3a + 6b = 114........(5)
Substracting (3) from (5)
3a - 3a + 6b - (-b) = 114 - 9
6b +b = 105
7b = 105
b = 105/7
b = 15
And 3a - b = 9 putting b = 15
3a - 15 = 9
3a = 15+9
3a = 24
a = 24/3
a = 8
And
x^2 = a
x^2 = 8
x = √8
x = √(4×2)
x = 2√2
Also y^2 = b
y^2 = 15
y = √15
Answer:
The amount after 4 years = $ 16198.87
Step-by-step explanation:
Points to remember
Compound interest
A = P[1 + R/n]^nt
Were A - Amount
P - Principle
R - Rate of interest
t - Number of years
n - Number of times compounded
<u>To find the amount</u>
Here P = $11,800, R = 8% = 0.08, t = 4 years and n = 4 times
A = P[1 + R/n]^nt
= 11800[1 + 0.08/4]^(4 * 4)
= 16198.87
Therefore amount after 4 years = $ 16198.87