What is the factored form of 2x2 + x-3?
1 answer:
Answer:
Step-by-step explanation:
a = 2, b = 1, c = -3
We need to factor this by finding the product of a and c, then from there find which factors of a * c will either add or subtract to give us b.
a * c = 6 and the factors of 6 and 1 and 6, 2 and 3. Well, 6 - 1 doesn't equal 1 and neither does 6 + 1. So our factors are 3 and 2. In order to combine those to get a 1 (our b), we will subtract 2 from 3 since 3 - 2 = 1. That means that 3 is positive and 2 is negative. Filling in the formula with 3 and 2 in place of 1 looks like this (always remember to put the absolute value of the largest number first):
Group the first 2 terms together and the second 2 term together in order to factor:
and factor out what's common in each set of parenthesis.
Notice that when we factor out a -1 from the second set of parenthesis, we can distribute it back in to get the equation we started with. We know that factoring by grouping "works" if what is inside both sets of parenthesis is exactly the same. Ours are identical: (2x + 3). That is common now, and can be factored out:
That matches your first choice
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Answer:
1. 121 π unit²
2. 143°
3. 151 unit²
Step-by-step explanation:
1.
Area of a circle is given by the formula A = πr²
where
A is the area,
r is the radius of the circle
From the given diagram, we can see that the radius is 11, hence the area will be:
The answer is units^2
2.
The unshaded secctor and the shaded sector equals the circle. We know that circle is 360°. The unshaded sector has an angle of 217°. So the shaded part will be 360 - 217 = 143°
The measure of the central angle of the shaded sector is 143°
3.
Area of a sector is given by the formula
Where
is the central angle of the sector (in our case it is 143°)
r is the radius (which is 11)
Plugging in all the info into the formula we have:
<em>rounding to the nearest whole number, it is </em>151 units^2