i tried these quesions so manytimes , but i just cant get he rigt answer !
1.) 4(2-a)^2-81
2.) -(x-y)^3
3.)3x^2-27(2-x)^2
4.) 9(y-1)^2-25
I can help you solve these equations step by step. Let's start with the first one:
1.) 4(2-a)^2 - 81
To solve this equation, we need to apply the order of operations, also known as BIDMAS (Brackets, Indices, Division, Multiplication, Addition, and Subtraction).
a. First, we start by expanding the square inside the brackets:
4(4 - 4a + a^2) - 81
b. Next, we simplify the equation by multiplying 4 with each term inside the brackets:
16 - 16a + 4a^2 - 81
c. Combine like terms:
4a^2 - 16a - 65
Now, let's move on to the second equation:
2.) -(x-y)^3
To simplify this expression, we need to apply the cube rule:
a. Start by expanding the cube inside the brackets:
-(x^3 - 3x^2y + 3xy^2 - y^3)
b. Since this is a negative sign outside the brackets, it affects every term inside:
-x^3 + 3x^2y - 3xy^2 + y^3
Let's move on to the third equation:
3.) 3x^2 - 27(2-x)^2
To solve this equation, we start by applying the order of operations.
a. Expand the square inside the brackets first:
27(4 - 4x + x^2)
b. Multiply 27 by each term inside the brackets:
108 - 108x + 27x^2
Finally, let's solve the last equation:
4.) 9(y-1)^2 - 25
Following the order of operations, we can simplify this equation as follows:
a. Expand the square inside the brackets:
9(y^2 - 2y + 1) - 25
b. Multiply 9 by each term inside the brackets:
9y^2 - 18y + 9 - 25
c. Combine like terms:
9y^2 - 18y - 16
These are the simplified forms of the given equations.