The equation in standard form is 2x^2 + 7x - 15=0. Factoring it gives you (2x-3)(x+5)= 0. That's the first one. The second one requires you to now your formula for the axis of symmetry which is x = -b/2a with a and b coming from your quadratic. Your a is -1 and your b is -2, so your axis of symmetry is
x= -(-2)/2(-1) which is x = 2/-2 which is x = -1. That -1 is the x coordinate of the vertex. You could plug that back into the equation and solve it for y, which is the easier way, or you could complete the square on the quadratic...let's plug in x to find y. -(-1)^2 - 2(-1)-1 = 0. So the vertex is (-1, 0). That's the first choice given. For the last one, since it is a negative quadratic it will be a mountain instead of a cup, meaning it doesn't open upwards, it opens downwards. Those quadratics will ALWAYS have a max value as opposed to a min value which occurs with an upwards opening parabola. This one is also the first choice because of the way the equation is written. There is no side to side movement (the lack of parenthesis tells us that) so the x coordinate for the vertex is 0. The -1 tells us that it has moved down from the origin 1 unit; hence the y coordinate is -1. The vertex is a max at (0, -1)
Answer:
Step-by-step explanation:
x*0.75=36
x=36/0.75=48 $
128.309728
add all numbers together and divide by 50(there are 50 numbers)
find the difference of each number and 67.92(the mean)
add all these numbers together and divide by 50
Answer:
x= 16
Step-by-step explanation:
First, you want to distribute each side! (you're gonna wanna learn this because you will be having to do it for the next 3 years no joke it sucks)
7(x+2) can be distributed as 7x+14 after multiplying 7 times x and 7 times 2, and 6(x+5) can be distributed as 6x+30.
Now, you have to get the x on one side to solve for x (so like x=__).
To do this, look at the equation as of now. 7x+14=6x+30.
We can minus 14 and bring that to the right, and minus 6x and bring that to the left to separate the x's and the regular numbers.
Now we have 16=x (or x=16).
What’s is it about can you tell me.?