The first 3 are examples of the difference of 2 squares so you use the identity
a^2 - b^2 = (a + b)(a - b)
x^2 - 49 = 0
so (x + 7)(x - 7) = 0
so either x + 7 = 0 or x - 7 = 0
giving x = -7 and 7.
Number 7 reduces to 3x^2 =12, x^2 = 4 so x = +/- 2
Number 8 take out GCf (d) to give
d(d - 2) = 0 so d = 0 , 2
9 and 10 are more difficult to factor
you use the 'ac' method Google it to get more details
2x^2 - 5x + 2
multiply first coefficient by the constant at the end
that is 2 * 2 = 4
Now we want 2 numbers which when multiplied give + 4 and when added give - 5:- -1 and -4 seem promising so we write the equation as:-
2x^2 - 4x - x + 2 = 0
now factor by grouping
2x(x - 2) - 1(x - 2) = 0
(x - 2) is common so
(2x - 1)(x - 2) = 0
and 2x - 1 = 0 or x - 2 = 0 and now you can find x.
The last example is solved in the same way.
Answer:
Area=Base length x Height
Area= O x g.
Answer:
6.87 x 10^15
Step-by-step explanation:
6.87 * 10^15 = 6870000000000000
Hope this helps :)
P.S. Message me if this is wrong
P.P.S Hope you have a great day!
Equation: L=P*R*T
P=100
R=1.5%=0.015
T=5
Multiply and you get 7.5 as the interest.
Answer:
0.5 < x < 16.5
Step-by-step explanation:
The third side of the triangle must be longer than the difference of the other two sides:
x > (8.5 -8.0)
x > 0.5
And it must be shorter than their sum:
x < (8.5 +8.0)
x < 16.5
The third side must be in the range ...
0.5 < x < 16.5
_____
These limits are a direct consequence of the triangle inequality, which requires the sum of the two shortest sides exceed the length of the longest side.
