1. Find the number that must divide each term in the equation so that the equation can be solved by the method of completing the square: 5x^2 - 7x = 20
which is it???
[a] 20
[b] 5
[c] -7
[d] x
2007-10-07 16:22:27 · 8 answers · asked by vennysweetgirl21 3 in Science & Mathematics ➔ Mathematics
b
2007-10-07 16:25:36 · answer #1 · answered by Anonymous · 0⤊ 0⤋
5
2007-10-07 23:27:44 · answer #2 · answered by Ford 1 · 0⤊ 0⤋
Later, you will learn that you can complete the square without dividing the equation.
However, for now, you will find it much easier to turn the equation to a square if the coefficient of x^2 is itself a square.
1 is a square.
Therefore, if you divide by 5, you will be left with:
x^2 - 1.4 x = 4
From here, solving by completing the square is much easier.
You are looking for a number (call it a) so that 2a = 1.4
a = 0.7
square that number: you get 0.49
add it to both sides:
x^2 - 1.4 x + 0.49 = 4.49
(x - 0.7)^2 = 4.49
x - 0.7 = â4.49
x = 0.7 + â4.49
2007-10-07 23:30:50 · answer #3 · answered by Raymond 7 · 0⤊ 0⤋
You divide the whole equation by 5
2007-10-07 23:28:14 · answer #4 · answered by queentriplet1 2 · 0⤊ 0⤋
b)5
2007-10-07 23:26:13 · answer #5 · answered by john 4 · 0⤊ 0⤋
5, the leading coefficient must be 1 in order to complete the square
2007-10-07 23:28:01 · answer #6 · answered by charliehorse1967 2 · 0⤊ 0⤋
(B) 5
2007-10-07 23:25:45 · answer #7 · answered by T 2 · 0⤊ 0⤋
It's [d] x.
2007-10-07 23:27:40 · answer #8 · answered by ravenna12 2 · 0⤊ 0⤋