Answer:
- (x, y) = (3, 5)
- (x, y) = (1, 2)
Step-by-step explanation:
A nice graphing calculator app makes these trivially simple. (See the first two attachments.) It is available for phones, tablets, and as a web page.
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The usual methods of solving a system of equations involve <em>elimination</em> or <em>substitution</em>.
There is another method that is relatively easy to use. It is a variation of "Cramer's Rule" and is fully equivalent to <em>elimination</em>. It makes use of a formula applied to the equation coefficients. The pattern of coefficients in the formula, and the formula itself are shown in the third attachment. I like this when the coefficient numbers are "too messy" for elimination or substitution to be used easily. It makes use of the equations in standard form.
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1. In standard form, your equations are ...
Then the solution is ...

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2. In standard form, your equations are ...
Then the solution is ...

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<em>Note on Cramer's Rule</em>
The equation you will see for Cramer's Rule applied to a system of 2 equations in 2 unknowns will have the terms in numerator and denominator swapped: ec-bf, for example, instead of bf-ec. This effectively multiplies both numerator and denominator by -1, so has no effect on the result.
The reason for writing the formula in the fashion shown here is that it makes the pattern of multiplications and subtractions easier to remember. Often, you can do the math in your head. This is the method taught by "Vedic maths" and/or "Singapore math." Those teaching methods tend to place more emphasis on mental arithmetic than we do in the US.
Answer: See explanation
Step-by-step explanation:
Number of marbles = 400
Anthony sells 1/4 of the marbles to Jayveon. This will be:
= 1/4 × 400
= 100 marbles
Anthony gives 10% to Abdul. Abdul will have:
= 10% × 400
= 0.1 × 400
= 40 marbles
He gave 10 marbles to his little brother.
The number of marbles that Anthony has left will be:
= 400 - (100 + 40 + 10)
= 400 - 150
= 250 marbles
Well first you would find a common denominator which would be 1w and then since you multiplied 4 by 3 to get to 12 you multiply 3 by 3 which is 9. So then you would have 9/12 + 1/12 which = 10/12
You know that there is a right angle which equals 90 degrees, you take 90 + 67 +37 which equals 194. You have 2 x's so it should equal 2x. Then you take 194 divided by 2, and you should have the answer to what x equals