Melody

Ok i can also see your point.

I might try it on other calcs when I get home.  If the web2 calc treats it differently from all the others I will send this thread to admin. :)

No I am not talking about your quadratic problem lol.

Maybe the other guy is. :)

Different calcs work differently I do not know of any standardized meaning of what +/- means.

If someone uses a tool in a test it is up to them to understand the nuances of the tool. Tell your student this and tell him to use (-9)^2.  That has a specifically defined meaning.

-9 is interpreted correctly as -1×9

-9^2= -1×9^2 = -1×81 = -81

However

(-9)^2=(-1×9)×(-1×9)=+81

No the web2 calc is correct.

If it did it your way then

10 - 3^2 would equal 10 +9  which is obviously nonesense.

Multiply both sides by 35. ☺

The 35s on the right wiĺl cancel out.  

Well you cannot simplify except by taking away the brackets.

Those brackets are meaningless and mildly annoying so get rid of them.

If you are meant to factorise then take out the 8

8(x^2-16)

Now you have a difference of 2 squares.

8(x-4)(x+4)

3. A bank teller counted 100 peso and 50 peso bills. ths totaled to 117 bills worth 9950 pesos. how many of each type did she have?

Let

F be the number of fiftties and

H be the number of hundreds

F+H=117

100H+50F=9950

Can you take it from there :)

I do not understand the first one.

second one

2. Mang Asyong sells sago in 4 kilo and 3 kilo containers. with much demand for sago he sold 30 containers containing 100 kilos. how many of each type did he sell?

Let

x be the number of 4kg containers and

y be the number of 3Kg containers

4x+3y=100      and    x+y=30

Can you take it from there?

Two great answers!!

What a fabulous diagram Heureka,