-3 • (5x + 2y = 7)
-15x - 6y = -21
-2x + 6y = 9
__________
-17x = -12
x = 12/17
5(12/17) + 2y = 7
2y = 7 - 60/17
2y = 3.47
y = 1.735
Answer:
36years
Step-by-step explanation:
Let charity present age be x
Charity daughter present age be y
Charity husband present age be z
If the sum of their ages ten years to come is 117, then;
10+x+10+y+10+z = 117
30+x+y+z = 117
x+y+z = 87 ... 1
If charity is four times as old as her daughter, then;
x = 4y
y = x/4 ... 2
If she is also six years younger than her husband, then;
x = z- 6
z = x+6 .. 3
Substitute 2 and 3 into 1;
x + x/4 + (x+6) = 87
Multiply through by 4
4x + x + 4(x+6) = 4(87)
5x+4x+24 = 348
9x = 348 - 24
9x = 324
x = 324/9
x = 36
hence Charity is 36years old today
Answer:
Speed of a= 21 miles/hr
r = Speed of b= 7 miles/hr
Speed of a = 3r
Step-by-step explanation:
The cyclist are 112 miles apart
Time traveled by two = 4 hours
Speed of a = 3 * speed of b
If a cylcles 3 times More than b, then a will cover 3*distance of b
But speed = distance/time
Time = 4hours
Total distance=112
a = 3b
3b + b = 112
4b = 112
b = 112/4
b = 28 miles
a = 3b
a = 3*28
a = 84 Miles
They bought traveled 4 hours
Speed of a = 84miles/4 hours
Speed of a= 21 miles/hr
Speed of b = 28miles/4 hours
Speed of b = 7 miles/hr
A and E, they are basically at the same point around
