The answer is 31/40
because first you got cane both of the fraction to the same denominator.
72/80 + 70/80
Add 72+70=142.
142/80 change it to an mixed number and it will be 1 31/40 in simplest form.
Group 'em together
a
b
−
a
+
1
−
b
a
b
−
a
=
a
(
b
−
1
)
Notice that there will be a 1 as without it it'll simply be ab
1
−
b
=
1
(
1
−
b
)
Notice that it doesn't match with the upper one... so we'll change the signs
1
(
1
−
b
)
=
−
1
(
b−
1
)
(try to multiply them now!!
Jot them down in one expression
a
(
b
−
1
)
−
1
(
b
−
1
)
You get!!!!!!
(
a
−
1
)
(
b
−
1
)
-10, -1.75, -3/4, 1/2, 3, 9
_____________________________
-3/4 converts to -0.75,
and 1/2 converts to 0.5. With -10 being farthest from zero on the number line, it would be the smallest. -1.75 would be the second smallest. Keeping in mind that -3/4 converts to -0.75, it would be the 3rd smallest. 1/2, or 0.5 would be greater, as it is the smallest POSITIVE number. Then you do 3, as it as a whole number, but still not the greatest. 9 would be the greatest.
hope i was helpful;-)