Let...
x=the number of red bricks
y=the number of blue bricks
Since she bought a total of 100 bricks... x+y=100.
Because the total cost is $560... 5x+7y=560.
Using these two equations, we can use the substitution method to solve for x and y.
x+y=100 ------------------------> x=100-y
subtract y on both sides
Because x=100-y...
this is x
5x+7y=560 (second equation) equals 5( 100 - y )+7y=560
This equation we created has only one variable so we can solve it.
5(100-y)+7y=560
500-5y+7y=560
2y+500=560
2y=60
y=30 blue bricks
Because x=100-y... x=100-30=70 red bricks.
Answer:
Step-by-step explanation:
cosθ = 1.3/3.1
θ = arccos(1.3/3.1)
There is a 5/12 chance that the marble will be blue. The reasoning behind this is that if you count all the marbles it will equal 12. So then all you have to do is see how many blue marbles there are, put that as the numerator, and put 12 as the denominator.
Answer:
Pythagorean Theorem?
Step-by-step explanation:
c²= a² + b²