If a^2 + b^2 + c^2 = 2(a – b – c) – 3, then the value of 2a – 3b + 4c is:
(a) 1
(b) 7
(c) 2
(d) 3
If \(a^{2}+b^{2}+c^{2}=2(a-b-c)-3\), then the value of \(2 a-3 b+4 c\) is (a) 1 (b) 7 (c) 2 (d) 3
Share
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
Given the equation \(a^{2}+b^{2}+c^{2}=2(a-b-c)-3\), we can rewrite it as:
\[
a^2 + b^2 + c^2 – 2a + 2b + 2c + 3 = 0
\]
This equation can be rearranged to form perfect squares:
\[
(a^2 – 2a + 1) + (b^2 + 2b + 1) + (c^2 + 2c + 1) = 0
\]
The expressions on the left-hand side can be rewritten as the squares of binomials:
\[
(a – 1)^2 + (b + 1)^2 + (c + 1)^2 = 0
\]
For the sum of squares to be zero, each square must individually be zero. Thus, we have:
\[
(a – 1)^2 = 0, \quad (b + 1)^2 = 0, \quad (c + 1)^2 = 0
\]
Solving these equations gives:
\[
a = 1, \quad b = -1, \quad c = -1
\]
Substituting these values into the expression \(2a – 3b + 4c\):
\[
2(1) – 3(-1) + 4(-1) = 2 + 3 – 4 = 1
\]
Therefore, the value of \(2a – 3b + 4c\) is \(1\).
The correct answer is (a) 1.