Answer:
Step-by-step explanation:
You have 3 unknowns: a, b, and c. It's our job to find them algebraically. I'm going to start with the point where x = 0 and y = 7. You'll see why in a minute. Filling in the standard form of a quadratic
using (0, 7):
gives you that c = 7. We will use that value now when we write the next 2 equations. Now the point (-2, 19):
and
so
12 = 4a - 2b
Now for the next point (-1, 12):
and
so
5 = a - b
Now we have a system of equations (the 2 bold font equations) that we will solve by elimination:
12 = 4a - 2b
5 = a - b
Multiply the bottom equation by -4 to get a new system:
12 = 4a - 2b
-20 = -4a + 4b
Add those together to get rid of the a terms and end up with
-8 = 2b so
b = -4
Now we can sub in -4 for b to solve for a. I'm using the second bold type equation to do this:
5 = a - (-4) and
5 = a + 4 so
a = 1 and the equation for the quadratic function is
Answer:
267 and 322
Step-by-step explanation:
<h3>
Answer: No, this isn't a function.</h3>
Why not? Focus on the two points (0,2) and (0,4)
We have the x value x = 0 show up twice. Any time x repeats itself like this, it leads to "not a function" as the result.
In other words, the input x = 0 leads to multiple outputs y = 2 and y = 4 at the same time. A function is only possible if every x input leads to exactly one y output.
If you are a visual learner, then plot all of the points on the same xy grid. Then notice how (0,2) and (0,4) fail the vertical line test to show we don't have a function.
Side note: The y values can repeat themselves in a function.
A) -6a = 36
Divide both sides by -6 so that (a) is isolated.
a = -6
Check by plugging in -6 for a.
-6a=36
-6(-6)=36
36=36
So, a=-6
B) -9d=-72
Divide both sides by -9.
d = -72/-9
d = 8
Check work by plugging in 8 for d.
-9d=-72
-9(8)=-72
-72=-72
So, d=8
~Hope I helped!~
Answer:
cement by 5 Kg
Step-by-step explanation:
add the parts of the ratio, 5 + 4 + 1 = 10 parts
Divide the quantity of concrete by 10 to find the value of one part of the ratio.
110Kg ÷ 10 = 11Kg ← value of 1 part of ratio , thus
5 parts = 5 × 11Kg = 55Kg ← cement required
4 parts = 4 × 11Kg = 44Kg ← sand required
1 part = 11Kg ← gravel required
He requires 55Kg of concrete but only has 50Kg.
He requires 44Kg of sand and has 55Kg
He requires 11Kg of gravel and has 15Kg
Thus he is 5Kg short of cement.
