Answer:
Step-by-step explanation:
We first have to write the equation for the sequence, then finding the first five terms will be easy. Follow the formatting:
and we are given enough info to fill in:
and
and
or in linear format:
where n is the position of the number in the sequence. We already know the first term is -35.
The second term:
so
and
The third term:
and
so
and we could go on like this forever, but the nice thing about this is when we know the difference all we have to do is add it to each number to get to the next number.
That means that the fourth term will be -27 + 4 which is -23.
The fifth term then will be -23 + 4 which is -19. You can check yourself by filling in a 5 for n in the equation and solving:
and
so
Answer:
tanA = sinA / cosA = 3/5 / 4/5 = 3/4.
the probability is 5 out of 20
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.
