Let's solve this system thru the elimination method:
<span>-6x-3y=3 Mult. all terms by -1 to obtain 6x+3y = -3
-6x+7y=-7 Add your result to the second equation:
</span> 6x+3y = -3
-6x+7y=-7
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10y = -10, and so y = -1. Subst. -1 for y in the first equation and then solve the result for x. You'll find that x = 0.
Thus, the solution is (0, -1).
Let x represent the horse age
Let y represent the human age
Since the horse age and human age vary directly, we have the relation

Introducing an equality sign, we

Where K is a proportionality constant, evaluated as

Since a 5-year-old horse is equivalent to 15-year old human,
x = 5
y = 15
we have

Thus,

Thus, for a horse who has lived 16 years
x = 16
The lines never intersect or touch should be the answer.
Hope this helps/works.
A taxi ride where the total fare is $3, $2 for every mile travelled plus a $1 tip and the original cost of $20.
First write a formula that expresses the cost of the ride:
Total cost= Flat fee + Mileage + Tip
Now let's drop in what we know:
20= 3+2 (miles) +1 - we know the total cost is 20, the fee of 3, the tip of 1 and the cost per mile of 2. The only thing we don't know is the number of miles. So let's solve for that.
Subtract 3 and 1 from both sides to get:
16=2(miles)
Divide both sides by 2:
8=miles
Therefore, you traveled 8 miles.