Step-by-step explanation:
V should be written as (1/3) pi r^2 h
V = (1/3) pi r^2 h multiply by 3
3V = pi r^2 h Divide by pi
3V/ pi = r^2 h Divide by r^2
3V / (pi *r^2 ) = h
Explanation:
It helps to understand the process of multiplying the binomials. Consider the simple case ...
(x +a)(x +b)
The product is ...
(x +a)(x +b) = x² +(a+b)x + ab
If the <em>constant</em> term (ab) is <em>negative</em>, the signs of (a) and (b) are <em>different</em>.
If the constant term (ab) is <em>positive</em>, the signs of (a) and (b) will both match the sign of the coefficient of the linear term (a+b).
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Of course, the sum (a+b) will have the sign of the (a) or (b) value with the largest magnitude, so when the signs of (a) and (b) are different, the factor with the largest magnitude will have the sign of (a+b), the x-coefficient.
<u>Example</u>:
x² -x -6
-6 tells you the factors will have different signs. -x tells you the one with the largest magnitude will be negative.
-6 = -6×1 = -3×2 = ... (other factor pairs have a negative factor with a smaller magnitude)
The sums of these factor pairs are -5 and -1. We want the factor pair that has a sum of -1, the coefficient of x in the trinomial.
x² -x -6 = (x -3)(x +2)
Answer:
a. 3.2 cm
b. 6.25 km
Step-by-step explanation:
a.
(4 km)/(5 km) = 0.8
4 km is 0.8 of 5 km, so in the map it is 0.8 of 4 cm.
0.8 * 4 cm = 3.2 cm
Answer: 3.2 cm
b.
(5 cm)/(4 cm) = 1.25
5 cm is 1.25 times 4 cm, so it represents 1.25 * 5 km.
1.25 * 5 km = 6.25 km
Answer: 6.25 km
Answer:
D.
Step-by-step explanation:
The slopes of perpendicular lines are negative reciprocals. That means that their product is -1.
In option D, since the slopes are 1 and -1, their product is -1, and the lines are perpendicular.
Answer: D.
