gwenspooner85

In 2004 the percentage was 50%. In 2005 the percentage was 62%. 62-50/50=12/50=24%.

Oh I see...I didn't see the OP's working. However, I don't understand how the equation leading back to h/a=b/(x+y) proves that (x+h)^2+(y+h)^2=(a+b)^2.

I asked for how CPhill got that expression...

Can anybody else help?

The formula for number of handshakes is n(n-1)/2 where n is the number of people. Plug 31 for n into the equation.

n(n-1)/2

=31(31-1)/2

=31(30)/2

= 465 handshakes

Let a be the tens digit and b the ones digit. Then the two digit number is 10a+b. We then know that 10a+b+a+b=50. Simplifying, we get 11a+2b=50. Using guess and check, a must be 4 and b 3. Therefore the two digit number is 43.

The approximate conversion from miles to kilometers is 1.609. Multiply 150 by 1.609 to get 241.35, which rounds to the nearest whole number 241. Therefore the speedometer reads 241 km/h.

Um how is a person supposed to add all of that?

Look, it's okay if you need help but it's not okay to post 7 questions at once! It's an overload and just annoying. How do you expect a person to solve 7 problems for you at once? You're basically dumping your homework here.

We write an equation in slope intercept form based on the given points. The slope must be 2/3 using the slope formula. We then have y=2/3x+b. We plug in one of the points to find b.

y=2/3x+b

1=2/3(6)+b

1=4+b

b=-3

The equation is y=2/3x-3. We then convert it into standard form.

y=2/3x-3

-2/3x+y=-3

2x-3y=9

We use the given points to write an equation in slope intercept form. Using the slope formula, the slope of this line is 2/11. We currently have the equation y=2/11x+b. We plug in one of the points into the equation to find b. Using (8, 7) will be easier.

y=2/11x+b

7=2/11(8)+b

7=16/11+b

b=61/11

So the slope intercept equation we have is y=2/11x+61/11. We then convert it into standard form.

y=2/11x+61/11

-2/11x+y=61/11

2x-11y= -61

A+B+C=2+(-11)+(-61)=2-11-61= -70.