Question

ПОМОГИТЕ ПОЖАЛУЙСТА СРОЧНО ПРОШУ

Answer 1

-{x-y=5
-{x+2y=-1
-3y=6|:(-3)
y=-2
x+2=5
x=3

(-0,2m³np⁴)²*25mn³p=0,04m6n²p8*25mn³p=
m7n5p9

(14ab-9a²-3b²)-(-3a²+5ab-4b²)=
14ab-9a²-3b²+3a²-5ab+4b²=-6a²+b²+9ab

Answer 2

$9)\; \; \left \{ {{x-y=5} \atop {x+2y=-1}} \right.\ominus \left \{ {{x=5+y} \atop {-3y=6}} \right. \left \{ {{x=3} \atop {y=-2}} \right.\; \; \Rightarrow\; \; \; (3,-2)\\\\10)\; \; (-0,2m^3np^4)^2\cdot 25mn^3p=0,04m^6n^2p^8\cdot 25mn^3p=m^7n^5p^9\\\\(14ab-9a^2-3b^2)-(-3a^2+5ab-4b^2)=\\=14ab-9a^2-3b^2+3a^2-5ab+4b^2=9ab-6a^2+b^2$