Answer:
4x-9.
Step-by-step explanation:
-3x - 8 + 7x - 1
7x -3x=4x.
-8 -1= - 9.
4x-9
You can know a perfect square trinomial:
i) if the coefficient of a² = 1.
ii) If you divide the middle number coefficient by 2 and you square it you get the last term.
Take for example the first option:
For all the options, the coefficient of a² = 1
a² + 4a + 16.
Coefficient of a = 4.
4/2 = 2
2² = 4, this does not equal the last term so it is not a perfect square trinomial.
a² + 14a + 49.
Coefficient of a = 14.
14/2 = 7
7² = 49, this is equal the last term so it is a perfect square trinomial.
And the perfect square is (a +7)²
Similarly if you test the last option.
a² + 26a + 169.
Coefficient of a = 26.
26/2 = 13
13² = 169, this is equal the last term so it is a perfect square trinomial.
And the perfect square is (a +13)²
So the only two options are: a² + 14a + 49 and a² + 26a + 169.
Other options do not pass this test.
Answer:
Step-by-step explanation:
<u><em>Let's check it using Pythagorean Theorem:</em></u>
Where c is the longest sides, a and b are rest of the 2 sides
1) 9 , 40 , 46
=>
=> 
=> 2116 = 81 + 1600
=> 2116 ≠ 1681
So, this is not a Pythagorean Triplet
2) 16, 30 and 34
=>
=> 
=> 1156 = 256 + 900
=> 1156 = 1156
No need to check more as we've found the one which is not a Pythagorean Triplet.
Answer:
$75.6
Step-by-step explanation:
5%of 72 = 3.6
72+3.6 = 75.6
Answer:
x = 17.1
Step-by-step explanation:
Since this is a right triangle, we can use trig functions
cos theta = adj / hyp
cos 42 = x/23
23 cos 42 = x
17.09233 =x
Rounding to 1 decimal place
x =17.1
