Answer:
8
Step-by-step explanation:
x^2 - 8 = 7x
x^2 - 7x - 8=0
(x - 8)(x + 1)=0
x - 8= 0 x + 1=0
x=8 x= -1
8 is the positive solution
Answer:
Umm what do <em>I</em> answer there is nothing there
Step-by-step explanation:
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.
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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
Rational is a number that can be expressed as a ratio of two in tegers where denominator is not equal to 0 is called a rational number.