These techniques for elimination are preferred for 3rd order systems and higher. They use "Row-Reduction" techniques/pivoting and many subtle math tricks to reduce a matrix to either a solvable form or perhaps provide an inverse of a matrix (A-1)of linear equation AX=b. Solving systems of linear equations (n>2) by elimination is a topic unto itself and is the preferred method. As the system of equations increases, the "condition" of a matrix becomes extremely important. Some of this may sound completely alien to you. Don't worry about these topics until Linear Algebra when systems of linear equations (Rank 'n') become larger than 2.
Answer:
B: (4x - 7)(16x^2 + 28x + 49)
Step-by-step explanation:
64x^3-343 can be rewritten as 4^3x^3 - 7^3 or (4x)^3 - 7^3. This is the difference of two cubes. The appropriate formula for factoring such is
a^3 - b^3 = (a - b)(a^2 + ab + b^2). Therefore,
our (4x)^3 - 7^3 = (4x - 7)(16x^2 + 28x + 49). This is Answer B.
Answer: x=3/2
Step-by-step explanation:
Multiply the parentheses by 2/3. 9=2/3x+8.
Multiply both sides by 3 . 27=2x+24
Move the term. When moved to the left side it changes from positive to a negative. -2x=24-27.
-2x=-3
Divide both sides by -2
x=3/2 (x=1 1/2, x=1.5)
Answer:
The square root of 120 is 10.9545.
The square root of 30 is 5.47723.
10.9545 divided by 5.47723 is approximately 2.0000073
