Question

$(5w - 4)x^{3}$

Answer 1

Step-by-step explanation:

5wx³+64 is the correct answer...

Answer 2

$\boxed{\mathsf{(5x-4)^{3}=125x^{3}-300x^{2}+240x-64}}$

Or, $\boxed{\mathsf{(5w-4)x^{3}=5wx^{3}-4x^{3}}}$

Correct question:

Expand $\mathsf{(5x-4)^{3}}$

or, Evaluate $\mathsf{(5w-4)x^{3}}$

Solution 1.

• Let us know algebraic formula before we solve the problem.
• $\underline{\mathsf{(a-b)^{3}=a^{3}-3a^{2}b+3ab^{2}-b^{3}}}$

Now, $\mathsf{(5x-4)^{3}}$

$\mathsf{=(5x)^{3}-3\:.\:(5x)^{2}\:.\:4+3\:.\:5x\:.\:(4)^{2}-(4)^{3}}$

$\mathsf{=125x^{3}-3\:.\:25x^{2}\:.\:4+3\:.\:5x\:.\:16-64}$

$\mathsf{=125x^{3}-300x^{2}+240x-64}\:\mathbb{(Ans.)}$

Or, Solution 2.

Now, $\mathsf{(5w-4)x^{3}}$

• Apply the formula: $\underline{\mathsf{(a-b)c=ac-bc}}$

$\mathsf{=5wx^{3}-4x^{3}}\:\mathbb{(Ans.)}$