Answer
x/3 and 2 1/3
Step-by-step explanation:
Answer:
(d)
Step-by-step explanation:
Elimination is a good choice of solution method when the coefficient of a variable in one equation is a simple multiple of the coefficient of that same variable in the other equation. This is the case for the system in the last choice. (see attached)
__
We can consider the alternatives:
(a) substitution for y would work well
(b) the solution is given, no solution effort is required
(c) substitution for y would work well
(d) elimination would work well.
3(2x +3y) +(-6x +y) = 3(18) +(12) . . . . . eliminates x (y=6.6)
(2x +3y) -3(-6x +y) = (18) -3(12) . . . . . . eliminates y (x=-0.9)
No because it would be
if you knew that
ax^2+bx+c was a trinomial square, then the factored form would be
![( \sqrt{a}x+ \sqrt{c})^{2}](https://tex.z-dn.net/?f=%28%20%5Csqrt%7Ba%7Dx%2B%20%5Csqrt%7Bc%7D%29%5E%7B2%7D%20%20)
or
![( \sqrt{a}x- \sqrt{c})^{2}](https://tex.z-dn.net/?f=%28%20%5Csqrt%7Ba%7Dx-%20%5Csqrt%7Bc%7D%29%5E%7B2%7D%20%20)
so
if w^2-9w+81 is perfect square, factored form is either
![( \sqrt{1}x+ \sqrt{81})^{2}](https://tex.z-dn.net/?f=%28%20%5Csqrt%7B1%7Dx%2B%20%5Csqrt%7B81%7D%29%5E%7B2%7D%20%20)
or
![( \sqrt{1}x- \sqrt{81})^{2}](https://tex.z-dn.net/?f=%28%20%5Csqrt%7B1%7Dx-%20%5Csqrt%7B81%7D%29%5E%7B2%7D%20%20)
aka
![( x+9)^{2}](https://tex.z-dn.net/?f=%28%20x%2B9%29%5E%7B2%7D%20%20)
or
expand them
(x+9)^2=x^2+18x+81, wron middle term
(x-9)^2=x^2-18x+81 wrong
so it is not
Answer:
24
Step-by-step explanation:
Lets start by working out 80% of 30
80% x 30=24
so the student answered 24 questions correctly
The dimensions of the machine are 20,48 and 17. If each dimension is increased by a factor of x;
Then new dimensions are
20x, 48x and 17x
The sum of the dimensions are ;
20x + 48x + 17x = 200
85x = 200
x = 200/85
Therefore each dimension was increased by a factor of x,
The new dimension of the shortest side is 17” * 200/85 = 40
So the increase in the shortest side ;
40-17 = 23”