Question

1) 5(×-y)2; 2)3(×+y)2; 3)(5×-y2); 4)(3×+y)2 при ×=2,5,y=4,5​

Answer 1

1)5(2,5-4,5)=-20

2)3(2,5+4,5)2=42

3)(5×2,5-4,4×2)=3,5

4)(3×2,5+4,5)=12

Answer 2

It looks like you've provided four mathematical expressions and specified values for the variables x and y. Let's evaluate each expression using the given values:

1. $5 \cdot (x - y)^2$, where $x = 2.5$ and $y = 4.5$: $5 \cdot (2.5 - 4.5)^2 = 5 \cdot (-2)^2 = 5 \cdot 4 = 20$.

2. $3 \cdot (x + y)^2$, where $x = 2.5$ and $y = 4.5$: $3 \cdot (2.5 + 4.5)^2 = 3 \cdot 7^2 = 3 \cdot 49 = 147$.

3. $5x - y^2$, where $x = 2.5$ and $y = 4.5$: $5 \cdot 2.5 - 4.5^2 = 12.5 - 20.25 = -7.75$.

4. $(3x + y)^2$, where $x = 2.5$ and $y = 4.5$: $(3 \cdot 2.5 + 4.5)^2 = (7.5 + 4.5)^2 = 12^2 = 144$.

So, when $x = 2.5$ and $y = 4.5$:

1. $5 \cdot (x - y)^2 = 20$.
2. $3 \cdot (x + y)^2 = 147$.
3. $5x - y^2 = -7.75$.
4. $(3x + y)^2 = 144$.