Answer:a.100+(hx25)
b.120+(hx20)
c.4 hours
h=hours
Step-by-step explanation:
Answer:
xy (less than or equal to sign) 4
-4x + 9y = 9...............(1)
x - 3y = -6 Multiply through by 3:-
3x - 9y = -18..............(2)
adding equations (1) and (3):-
-x = -9
x = 9
Substitute for x in equation (1)
-4(9) + 9y = 9
-36 + 9y = 9
9y = 45
y = 5
Answer is x = 9 and y = 5
Answer:
213
Step-by-step explanation:
The circumference of the wheel is given by
C=2πr=πd
Where d is diameter, r is radius and c is circumference
The number of revolutions N multiplied by circumference should yield the total distance
N*πd= Distance
Given distance of 20, 000 cm and diameter of 30 cm
30πN=20000
Making N the subject of formula
N=20000/(30π)=212.20659078919378102517835116335248271261
Rounded off, about 213 revolutions are required
Answer:
15x + 9
Step-by-step explanation:
9(3x + 8) – 3(4x + 21)
Multiply
27x + 72 - 12x - 63
Combined like terms
27x - 12x = 15x 72 - 63 = 9
15x + 9