Answer:
w=5
Step-by-step explanation:
the triangle has the same size of area as the side of the rectangle so therefore 5
5x-23=87
add 23 to both sides
5x=110
divide both sides by 5
x=22
To check your answer...
5(22)-23=87
110-23=87
87=87
Answer:
a) not proportional
b) proportional; k = 
Step-by-step explanation:
a) for any proportional equation, the line must pass through the origin. The equation in a) is y = 4x + 1, and the '+1' is the y-intercept. This means that the line does not pass through the origin, so x and y cannot increase by the same amount (i.e. they are not proportional).
Another way to determine this is is to use the y = kx base. If you have an equation that fits that it's likely proportional.
Here, if the equation was only y = 4x then it'd be proportional because u can see that k = 4. This is not the equation though, and the 4x + 1 doesn't fit to the y = kx formula so it can't be proportional.
b) straight away you can see that there's no 'c' term (y = mx + c) which means the y-intercept is 0, so the line passes through the origin. While this does not immediately mean the line is proportional, you can make sure that it is by checking it fits with the y = kx equation.
y = -(3/5)x fits with y = kx, with k being -3/5
Realize that since 2x and 3x - 1 are equal to each other, they are also equal to y. This means that we can craft two equations, y = 2x and y = 3x - 1.
When you want to solve a systems of equations via a graph, you need to plot both equations on a graph and determine the x- and y-value of where the lines intersect. In this case, we would plot both y = 2x and y = 3x - 1. These lines intersect at the point (1, 2).
Since we are trying to find the day the bullfrog will be able to eat the entire population, or x, we are going to use the x-value of our point as our answer. Thus, our answer is 1 day.