9514 1404 393
Answer:
a. (-1/2, 5)
Step-by-step explanation:
The coefficients of x have opposite signs, so the x-terms can be eliminated by adding the two equations.
(2y -12x) +(3y +12x) = (16) +(9)
5y = 25 . . . . . . simplify
y = 5 . . . . . . . . .divide by 5
This matches only answer choice A.
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<em>Check</em>
The other part of answer choice A is x = -1/2. We can test this to make sure it works:
2(5) -12(-1/2) = 16
10 + 6 = 16 . . . . . . true, the selected answer works OK
It would be 2(x+3)(x+1)=0
Explanation:
I used factor by grouping. You multiply the first term (2) by the last term (6). This gives you 12 then take the factors of 12 that add up to the middle term 8. You get 6 and 2.
It should look like 2x^2+6x+2x+6=0
when you do factor by grouping you factor the first two terms and then the last two terms separately. So you get (2x+2) and (x+3). (2x+2) could be factored into 2(x+1). Then you put everything together and get 2(x+3)(x+1)=0
The correct answer is B, sorry if it wasn't correct.
Find area on triangle:
A=(1/2)bh
A=(1/2)(8 units)(6 units)
A=(1/2)(48 units^2)
A=24 units^2
Just do the same for the rest of this page following the equation for the area of a triangle A=(1/2)(base)(height)
Find the error:
A=(1/2)bh
100m^2=(1/2)b(20m)
100m^2=(10m)b
10m=b
He forgot to multiply bh by 1/2
Area of parallelogram:
A=bh
A=(3 units)(3 units)
A= 9 units^2
The red line is the height and the bottom of the parallelogram is the base, just count the squares. Imagine cutting the parallelogram at the red line and moving that triangle piece to the other side, it’ll make a rectangle, that’s why the equation is the same.
