Step-by-step explanation:
All the 5 rows of the coefficient matrix (since it is of order 5×8) will have a pivot position. The augmented matrix obtained by adding a last column of constant terms to the 8 columns of the coefficient matrix will have nine columns and will not have a row of the form [0 0 0 0 0 0 0 0 1]. So the system is consistent.
The new square has length: 10 + l, where l is the original length of the square, and it's area is (10 + l)^2;
So, we solve the equation: 3 x l^2 = (10 + l)^2;
Then, 3 x l^2 = 100 + 20 x l + l^2;
Finally, 2xl^2 - 20xl - 100 = 0; / ÷2;
l^2 - 10l - 50 = 0 (we use the quadratic equation formula);
The only positive solution is l = 5(1+ \sqrt{3} );
Answer:
(3 x + 5) (x + 5)
Step-by-step explanation:
Factor the following:
3 x^2 + 20 x + 25
Hint: | Factor 3 x^2 + 20 x + 25 by finding factors of 3×25 whose sum is 20.
Factor the quadratic 3 x^2 + 20 x + 25. The coefficient of x^2 is 3 and the constant term is 25. The product of 3 and 25 is 75. The factors of 75 which sum to 20 are 5 and 15. So 3 x^2 + 20 x + 25 = 3 x^2 + 15 x + 5 x + 25 = 5 (3 x + 5) + x (3 x + 5):
5 (3 x + 5) + x (3 x + 5)
Hint: | Factor common terms from 5 (3 x + 5) + x (3 x + 5).
Factor 3 x + 5 from 5 (3 x + 5) + x (3 x + 5):
Answer: (3 x + 5) (x + 5)