The new parking lot must hold twice as many cars as the previous parking lot. The previous parking lot could hold 56 cars. So this means the new parking lot must hold 2 x 56 = 112 cars
Let y represent the number of cars in each row, and x be the number of total rows in the parking lot. Since the number of cars in each row must be 6 less than the number of rows, we can write the equation as:
y = x - 6 (1)
The product of cars in each row and the number of rows will give the total number of cars. So we can write the equation as:
xy = 112 (2)
Using the above two equations, the civil engineer can find the number of rows he should include in the new parking lot.
Using the value of y from equation 1 to 2, we get:
x(x - 6) = 112 (3)
This equation is only in terms of x, i.e. the number of rows and can be directly solved to find the number of rows that must in new parking lot.
it's plural so axes*
and in pilar coordinates, the axes are circular so they never intersect but the centre point is still called origin.
If tan0=-3/4 and 0 is in quadrant IV, cos20= (33/25, -17/25, 32/25, 7/25, 24/25?) and tan20= (24/7, -24/7, 7/25, -7/25, 13/7, -1
Oksana_A [137]
Answer:
- cos(2θ) = 7/25
- tan(2θ) = -24/7
Step-by-step explanation:
Sometimes, it is easiest to let a calculator do the work. (See below)
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The magnitude of the tangent is less than 1, so the reference angle will be less than 45°. Then double the angle will be less than 90°, so will remain in the 4th quadrant, where the cosine is positive and the tangent is negative.
You can also use the identities ...
cos(2θ) = (1 -tan(θ)²)/(1 +tan(θ)²)
cos(2θ) = (1 -(-3/4)²)/(1 +(-3/4)²) = ((16-9)/16)/((16+9)/16)
cos(2θ) = 7/25
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tan(2θ) = 2tan(θ)/(1 -tan(θ)²) = 2(-3/4)/((16-9/16) = (-6/4)(16/7)
tan(2θ) = -24/7
The easy way to think about this is what number comes between 5 and 7? The answer is 6 (but we have to consider that it's negative in this case.) So the answer is -6 Another way to look at it is with a number line (not to "Which number is greater than -7 and less than -5"? scale.)<===(-7)==(-6)==(-5)==(-3)==(-2)==(-1)==(0)==(1)==>Notice how -6 comes between the two numbers. -6 is larger than -7 (it's "less negative" -- "Which number is greater than -7 and less than -5"? closer to zero) -6 is less than -5 (it's "more negative" -- further away from zero)
