Answer:
We are given that:
variables x and y vary directly, this means that:
y = kx where k is the constant of proportionality
Now, we are also given that:
y = 45 at x = 40.
We will use these values and substitute in the above relation to get k as follows:
y = kx
45 = 40k
k = 45/40 = 9/8 = 1.125
Based on the above calculations, the equation that relates x and y is:
y = 1.125x
Step-by-step explanation:
x is less than or equal to -4 or x is greater than or equal to 5
x <= -4 or x>= 5
There is no intersection of both inequalities when we graph it in number line So, we write the interval notation separately for each inequality
for x<=-4 , x starts at -4 and goes to -infinity because we have less than symbol. Also we have = sign so we use square brackets
Interval notation is (-∞ , -4]
for x>= 5 , x starts at 5 and goes to infinity because we have greater than symbol. Also we have = sign so we use square bracket at 5
Interval notation is [5 , ∞)
Now combine both notation by a 'U' symbol Union
(-∞ , -4] U [5 , ∞)
24 can only go into 64 about 2 times.