The first coefficient is 2 and the last term is 6. They multiply to 2*6 = 12.
Now we must find two factors of 12 that add to 7 (the middle coefficient).
Through trial and error, you should find that:
3*4 = 12
3+4 = 7
So 3 and 4 are the numbers we're after. We'll split the 7m into 3m+4m and use the factor by grouping method as shown in the steps below.
2m^2 + 7m + 6
2m^2 + 3m + 4m + 6
(2m^2 + 3m) + (4m + 6)
m(2m + 3) + 2(2m + 3)
(m + 2)(2m + 3)
(2m + 3)(m + 2)
The order of the factors doesn't matter since something like 2*3 is the same as 3*2.
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Verifying the answer:
You can use technology like you did to check the answer, but here's one way to do it without a calculator.
(2m + 3)(m + 2)
n(m + 2) ...... let n = 2m+3
mn + 2n .... distribute
m( n ) + 2( n )
m(2m+3) + 2(2m+3) .... plug in n = 2m+3
m*2m + m*3 + 2*2m + 2*3 .... distribute
2m^2 + 3m + 4m + 6
2m^2 + 7m + 6
We arrive back at the original trinomial, so we have confirmed the answer.
6 feet * 7 feet = 42 feet²
18 feet * 21 feet = 378 feet²
42 feet² was painted for $52
1 feet² will be painted for $52/42
378 feet² will then be painted for: ($52/42) * 378
= $468
Hence 18 feet by 21 feet will be painted for $468
Hope this helps.
Answer:
4(2x+6)=32 x= 1
Step-by-step explanation:
multiply 4 to 2x and 6= (8x+24)=32
then subtract 24 from 32 = 8
then divide 8 from both sides
8x/8=8/8
x=1
Step-by-step explanation:
LHS:
\frac{1}{1+\sqrt{2}}+\frac{1}{\sqrt{2}+\sqrt{3}}+\frac{1}{\sqrt{3}+\sqrt{4}}+\ldots \ldots \ldots \ldots \ldots+\frac{1}{\sqrt{8}+\sqrt{9}}1+21+2+31+3+41+……………+8+91
Rationalizing the denominator, we get
\Rightarrow\left(\frac{1}{1+\sqrt{2}} \times \frac{1-\sqrt{2}}{1-\sqrt{2}}\right)+\left(\frac{1}{\sqrt{2}+\sqrt{3}} \times \frac{\sqrt{2}-\sqrt{3}}{\sqrt{2}-\sqrt{3}}\right)+\left(\frac{1}{\sqrt{3}+\sqrt{4}} \times \frac{\sqrt{3}-\sqrt{4}}{\sqrt{3}-\sqrt{4}}\right)+\cdots \ldots+\left(\frac{1}{\sqrt{8}+\sqrt{9}} \times \frac{\sqrt{8}-\sqrt{9}}{\sqrt{8}-\sqrt{9}}\right)⇒(1+21×1−21−2)+(2+31×2−32−3)+(3+41×3−43−4)+⋯…+(8+91×8−98−9)
We know that,
\left(a^{2}-b^{2}\right)=(a+b)(a-b)(a2−b2)=(a+b)(a−b)
Now, on substituting the formula, we get,
=\frac{1-\sqrt{2}}{1-2}+\frac{\sqrt{2}-\sqrt{3}}{2-3}+\frac{\sqrt{3}-\sqrt{4}}{3-4}+\cdots \ldots \cdot \frac{(\sqrt{8}-\sqrt{9})}{8-9}=1−21−2+2−32−3+3−43−4+⋯…⋅8−9(8−9)
\Rightarrow \frac{1}{1+\sqrt{2}}+\frac{1}{\sqrt{2}+\sqrt{3}}+\frac{1}{\sqrt{3}+\sqrt{4}}+\cdots+\frac{1}{\sqrt{8}+\sqrt{9}}=(\sqrt{2}-1)+(\sqrt{3}-\sqrt{2})+(\sqrt{4}-\sqrt{3})+\cdots+(\sqrt{9}-\sqrt{8})⇒1+21+
