Answer:
The first one and the last one
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Answer:

Step-by-step explanation:
Given Equation:
Equation:1
Equation:2
Dividing Equation:2 by '3' both the sides:
or
Equation:3
Putting the vale of 'x' in Equation:1


Subtracting '3' both sides



Putting value of 'y' in Equation:3


The solution of the equations is :

Answer:
20x^6
Step-by-step explanation:
multiply bases and add exponents
Answer:
-12r² + 10xr - 15x + 34r - 24
Step-by-step explanation:
1. Organize it, variables first - as well as adding constants such as 4 and -7
(5x - 6r + 8) (2r - 3)
2. Start by multiplying the 5x by (2r - 3), then -6r, followed by 8
(10xr - 15x) + (-12r^2 + 18r) + (16r - 24)
3. Simplify
10xr - 15x - 12r² + 18r + 16r - 24
4. Order by greatest to smallest factorial
-12r² + 10xr - 15x + 18r + 16r - 24
5. Combine like variables
-12r² + 10xr - 15x + 34r - 24