Need math help (advanced math 11)?

Question

the temeperature at which water boils. T degrees celcius is a linear functon of the altitude "a" meters,at which it is heated. T =ma+b. In Banff AB the altitude is 1383 m and the water boils at 95 degrees celcius. On Mt. Logan BC the altitude is 5951m and the water boils at 80 degrees celcius.

determine the valued of m and b and write T as a function of a

plz help!!!!!!

Answer 1

You have two equations and two unknowns (m and b). Just plug in the values you do know (a and T). Then you solve for m or b in one expressions and plug it into the other to get the answer for one unknown. Then plug that answer into the other equation and you are done. You can always solve n number of equations with n unknowns by plugging in what you know, solving for one of the unknowns, and plugging it into the other expression.
(95C-b) / 1383 = m. Then plug that into the other expression for m, and you and solve for b. Then go back and plug in b and solve for m. Writing T(a) simply meas writing out your expression with the known values for m and b (with a as the unknown variable since you will know the rest of the function after you do the math.)

Answer 2

Banff:
95= m(1383)+b
Mt. Logan
80 =m(5951)+b
Multiply the Banff equation by (-1)
-95= -1383m-b
Add the Mt. Logan equation to it
-95=-1383m-b
80=5951m +b
--------------------Add
-15=4568m
m= -15/4568
Substitute this value for m into either original equation, to find a value for b. I'll use the Mt. Logan
equation.
T= ma+b
80= -15/4568 + b
b=80+15/4568
b=365440/4568 +15/4568
b=365455/4568

m= -15/4568
b=365455/4568

T=ma+b
T-b=ma
(T-b)/m = a

Answer 3

Hi,

Start by removing 'b' by subtraction:-

95 = 1883 m + b: Banff
80 = 5951m + b: Mt. Logan

-15 = 4568 m; then m = -(15/4568) = - 0.00328

then 80 = 5951 x (-0.00328) + b
= - 19.519

b= 99.519

so that T= - 0.00328 m + 99.519

Answer 4

Assuming Jack's numbers are correct (I did not check them), just substitute them for m and b in the equation T=ma+b, and the equation you will get expresses T as a function of a.

Answer 5

If you really cannot find a good teacher, I suggest that you try WiZiQ. I picked up this list of math teachers, who are willing to teach on the Internet:

http://www.wiziq.com/teachers/mathematics

You can also find teachers for specific topics and levels in subjects. e.g.:

http://www.wiziq.com/teachers/5th-8th-Grade-Elementary-Math

Hope this helps

Answer 6

using system of equations i found that
m= -15/4568
b= 1970755/4568

i dont know how to do functions sorry