25q + 10d = 425
q + d = 20
First thing's first, picture 4 quarters. Do you know how much these 4 quarters are worth? Obviously, you'd answer one dollar, but take the time to think about how exactly you came up with this answer.
"Well, it's simple," you might think, "Multiply 0.25 by 4."
Similar to this train of thought, the first equation is formulated by doing exactly that. 'q' represents an unknown number of quarters, and 'd' an unknown number of dimes. We use 25q and 10d, because, well, we're multiplying their value by the number of coins. They're equivalent to 425 because the 20 unknown coins make $4.25 (I converted it to cents to get rid of the pesky decimals, but if you want to keep it as dollars that works too).
Because the equation states that there are 20 coins in total, we know that we can make the equation 'q + d = 20' since there are 20 quarters and dimes in total.
Let me know if you need any further explanation :)
-T.B.
The equation of the vertical parabola in vertex form is written as
Where (h, k) are the coordinates of the vertex and p is the focal distance.
The directrix of a parabola is a line which every point of the parabola is equally distant to this line and the focus of the parabola. The vertex is located between the focus and the directrix, therefore, the distance between the y-coordinate of the vertex and the directrix represents the focal distance.
Using this value for p and (3, 1) as the vertex, we have our equation
Answer:
b = 10
Step-by-step explanation:
The area (A) of a triangle is calculated as
A = 
bh ( b is the base and h the height )
Here h = 3x + 15 and A = 15x + 75, thus
× b × (3x + 15) = 15x + 75
Multiply both sides by 2 to clear the fraction
b(3x + 15) = 30x + 150
Divide both sides by (3x + 15)
b = 
← factor numerator and denominator
= 
← cancel the factor (x + 5) on numerator/denominator
= 
= 10
(1, -6) and (-5, 2)
Distance between 1 and -5 = 6
Distance between -6 and 2 = 8
6²+8²=x² (PYTHAGOREAN THEOREM)
36+64=x²
x² = 100
x = 10
Note: Not -10 because <em>distance cannot be negative.</em>
<h3>
Answer:</h3>
5/2
<h3>
Step-by-step explanation:</h3>
The ratio of perimeters is the same as the ratio of corresponding sides:
... (140 cm)/(56 cm) = 5/2
