Answer:
c
Step-by-step explanation:
If you would like to know how many hours will Lena need to work before she can afford to buy the computer, you can calculate this using the following steps:
$900 - $473 = $427
$427 / $7 = 61 hours of yard work
Result: Lena will need to work 61 hours before she can afford to buy the computer.
Question:
If cos(θ) =-8/17 and sin(θ) is negative, then sin(θ) = ___ and tan(θ) =___.
Answer:


Step-by-step explanation:
Given
cos(θ) =-8/17
Required
sin(θ) = __
tan(θ) =__
The first step is to determine the length of the third side
Given that

Where Adj and Hyp represent Adjacent and Hypotenuse

By comparison

Using Pythagoras

By Substitution


Subtract 64 from both sides


Take square roots of both sides




The question says that sin(θ) is negative; This implies that θ is in the third quadrant and as such

From trigonometry


Also from trigonometry






<span>4.5 g
56.25 g
Since the only type of measurement mentioned in this question is weight or mass, I'll assume that the percentage concentration is % m/m (mass/mass). For that type of concentration measurement, simply multiple the percentage by the total mass to get the mass of the desired substance. So
150 g * 3% = 150 g * 0.03 = 4.5g
For the amount of 8% solution with the same amount of dry substance, there's 2 ways of calculating the mass of solution.
First, use the ratio of percentages, multiplied by the mass of the original solution to get the desired amount of new solution:
3/8 * 150 g = 56.35 g
Or calculate it from scratch, like
4.5/X = 8/100
450/X = 8
450 = 8X
56.25 = X
In both cases, the result is that you desire 56.25 grams of 8% solution.</span>