CPhill

If x>0 and 2x^2-5x-12=0   factor this

(2x + 3)(x - 4) = 0

Setting each factor to 0, only the second factor produces an 'x" > 0, i.e.,   x = 4

13 / 25 = x / 100     cross-multiply

1300 = 25x           divide by 25

52 = x = 52%

Any positive number (except 1) could - theoretically - be used as a base.....but 10 and "e" are the most common....

Wow.....thanks h7....I didn't even know you could do that on this calculator!!....did you figure that out just fooling around with it ????

x=-2y-3

4y-x=9

Notice that we can substitute the first thing into the second....this gives

4x - (-2y - 3) = 9    simplify

6y + 3 = 9      subtract 3 from both sides

6y = 6            divide both sides by 6

y = 1       and subtituting this back into x = -2y - 3 ,  we find that x = -2(1) - 3   = -5

So our answer is x = -5 and y =1

You aleady have it in scientific notation.....

Just type  "factor(8820)"  into the onsite calculator.....

A cuboid has a length of 6cm, a with of 1.5cm, and a depth of 1.5cm . Work out the total surface area

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The surface area is

4(6 x 1.5) + 2(1.5 x 1.5) = 4(9) + 2(2.25) = 36 + 4.5 =  40.5cm²

Notice that if something decreases by 4%, it must only be equal to 96% (.96) of its original value...

Does that make sense ??

To find the answer, we need to take the square root of 4/9.....so...

√(4/9)= 2/3