Math Problem Statement
if 3x + 2y = 5 and xy = - 2 , find 27x³ + 8y³
Solution
We are given two equations:
We need to find the value of .
Step-by-Step Solution:
Step 1: Recognize the form of the expression.
The expression can be rewritten as:
Step 2: Use the identity for sum of cubes.
We use the identity for the sum of cubes:
Here, let and . So we have:
Step 3: Substitute and simplify.
From the first equation, we know that . Substituting this, we get:
Now, we calculate each term inside the parentheses:
- ( (3x)^2 =
Ask a new question for Free
By Image
Drop file here or Click Here to upload
Math Problem Analysis
Mathematical Concepts
Algebra
Cubic Expressions
Sum of Cubes
Formulas
Sum of cubes identity: a^3 + b^3 = (a + b)(a^2 - ab + b^2)
Theorems
Sum of Cubes Theorem
Suitable Grade Level
Grades 9-11