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3 years ago

5

(3a3 − 5b3) + _ a3 + _b3 = (a3 + b3).

1 answer:

Harlamova29_29 [7]3 years ago

7 0

3a^3-5b^3+xa^3+yb^3=1a^3+1b^3
replace a^3 with z
replace b^3 with v (to make it easier to see)
3z-5v+xz+yv=z+v
3z+xz+yv-5v=1z+v

the terms match them
3z+xz=1z
divide both sides by z
3+x=1
minus 3
x=-2

yv-5v=1v
dividie both sides by v
y-5=1
addd 5 to both sides
y=6

(3a^3-5b^3)+ <u>-2</u> a^3 +<u>6</u> b^3=(a^3+b^3)

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8 0

3 years ago

Read 2 more answers