If 25 and 9 are expressed in feet the area is 225 sq ft.
Multiply by 9/5 and then add 32 to convert from C to F. 25X9/5+32=77
Yes you can. It has 25x9 gearing. That means it has a cassette in the rear wheel. Eastern cassette's click very loud if you are into that sort of thing.
25x1=25 25x2=50 25x3=75 25x4=100 25x5=125 25x6=150 25x7=175 25x8=200 25x9=225 25x10=250
In the future, ask four questions as four separate questions to limit confusion. 6x7y4(2x4 - 5xy) could be written as 6x8y4(2x3 - 5y) Either way, once you carry out the multiplication, it becomes 12x11y4 - 30x8y5 I'm guessing the second problem is 25x9 - 10x3 + 5x3 since this website can't reproduce plus signs. That becomes 25x9 - 5x3 which factors to 5x3(5x6 - 1) x^2 and -x^2 cancel each other out, leaving 3549 - 12x which factors to 3(1183 - 4x) -7x^2 - 3x - 21 can be written as -(7x^2 + 3x + 21) but the solution isn't rational.
The perfect square factor of 50 is 25 and the perfect square factor for 90 is 9. The perfect square factors for 50x90 25x9. Of course we also have the other factors of 2 and 2x5.
Divide your rear sprocket into your front sprocket. Like 25x9. 25 divided by 9 = 2.77. so 2.77 to 1 is the drive ratio. If you go with a smaller sprocket like a 24 in the front but still a 9 in the back, you are lowering the gear ratio to 2.66 to 1. So your bike will be slower but easier to pedal. If you go with a 25 in the front and a 10 in the back, you end up with a 2.5 to 1 ratio. Don't confuse gear ratio with gear inches, that's a calculation including the wheel and sometimes the circumference of the tire.