posted by Wendy on .
At age 2, a cat or dog is considered 24 "human" years old. Each year after age 2 is equivalent to 4 "human" years. Fill in the expression [24 + X (a-2)] so that it represents the age of a cat or dog in human years. Copy the chart and use your expression to complete it.
Age 24+X(a-2) Age human years
I do not understand this math problem at all. It is actually my son's, who is in 7th grade, and the teacher did not explain anything either. If someone could just explain how to figure this out, that would be great.
Age 2 = 24 years
Age 3 = 24 years + 4 years = 28 years
Age 4 = 28 years + 4 years = 32 years
And so on --
I have not done Alegbra in 30 years so I am quite rusty with it. It just did not occur to me to change the 24 to 28 and so on. Does that mean that X equals (a-2), which would be 4, and that a would be 6?
With no definitions, it is difficult to know exactly what the teacher wanted but here is the best I can do. It is actually only a little more detailed explanation than the one given by Ms Sue and it takes into accout the factor of 4 years aging + the current age of the cat or dog.
Apparently, the teacher wants a to be the age of the cat or dog and X to be the constant of 4 years. At least that is my take on the problem.
The equation provided is
24 + X(a-2).
a = the age of cat or dog; i.e., 2, 3, 4, 5, 6, etc. in the equation.
X = 4 in the equation.
24 + 4(2-2) = 24+4(0)= 24+0=24
24 + 4(3-2) = 24+4(1)= 24+4=28
24 + 4(4-2) = 24+4(2)= 24+8=32
24 + 4(5-2) = 24+4(3)= 24+12=36
Thank you for having this online! My kid came home with this problem today. I have a Masters degree, but was still stumped! Time for some refresher courses...
Thank you for having this posted! My 7th grader had this exact problem and neither one of us could understand it.