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:
=(2x-3y+4z)+(9x-8y+7z)
=2x+9x-3y-8y+4z+7z
=11x-11y+11z
hope like the answer
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Answer:
1 pound = .73 dollars rounded.
Step-by-step explanation:
This is like a rate question. Speed is in miles / hour only the units for this question is pound / dollar.
pounds = 33
dollars = 45
1 pound is 33/45
1 pound = 0.73
Answer:
542
Step-by-step explanation:
We are required to find the sample size at 98% confidence interval in this question
E = 0.04
P* = 20% = 0.20
n = p* x (1-p)(Zα/2÷E)²
α = 1 - 0.98
= 0.02
To get Critical value
= 0.02/2 = 0.01
The critical value at 0.01 is 2.33
Inserting values into formula:
O.2 x 0.8(2.33/0.04)²
= 0.8 x 0.2 x 58.25²
= 542.89
The value of n must be an integer therefore the answer is 542.
