Answer:
{x = -3
, y=2 (Isolved for both variables be elimination)
Step-by-step explanation:
Solve the following system:
{3 x + 5 y = 1 | (equation 1)
7 x + 4 y = -13 | (equation 2)
Swap equation 1 with equation 2:
{7 x + 4 y = -13 | (equation 1)
3 x + 5 y = 1 | (equation 2)
Subtract 3/7 × (equation 1) from equation 2:
{7 x + 4 y = -13 | (equation 1)
0 x+(23 y)/7 = 46/7 | (equation 2)
Multiply equation 2 by 7/23:
{7 x + 4 y = -13 | (equation 1)
0 x+y = 2 | (equation 2)
Subtract 4 × (equation 2) from equation 1:
{7 x+0 y = -21 | (equation 1)
0 x+y = 2 | (equation 2)
Divide equation 1 by 7:
{x+0 y = -3 | (equation 1)
0 x+y = 2 | (equation 2)
Collect results:
Answer: {x = -3
, y=2
Answer:
27
Step-by-step explanation:
Answer:
(29-26) * 3 = 9
Step-by-step explanation:
I could only get number one which was; 1.75
5. The 5th figure will have 30 tiles.
6. The 6th figure will have 42 tiles.
7. The pattern is non-linear (quadratic).
8. The 20th figure can be made with 420 tiles.
_____
The Nth figure is made with n*(n+1) tiles. To answer question 8, you must solve
.. n(n +1) = 420
.. n^2 +n -420 = 0
.. (n +21)(n -20) = 0
.. n = 20 or -21 . . . . the negative solution is extraneous
