Answer:
D
Step-by-step explanation:
A negative discriminant indicates that the quadratic equation has no real roots.
Thus the graph does not touch or intersect the x- axis
The only graph that does not touch or intersect the x- axis is the fourth one
The system is:
i) <span>2x – 3y – 2z = 4
ii) </span><span>x + 3y + 2z = –7
</span>iii) <span>–4x – 4y – 2z = 10
the last equation can be simplified, by dividing by -2,
thus we have:
</span>i) 2x – 3y – 2z = 4
ii) x + 3y + 2z = –7
iii) 2x +2y +z = -5
The procedure to solve the system is as follows:
first use any pairs of 2 equations (for example i and ii, i and iii) and equalize them by using one of the variables:
i) 2x – 3y – 2z = 4
iii) 2x +2y +z = -5
2x can be written as 3y+2z+4 from the first equation, and -2y-z-5 from the third equation.
Equalize:
3y+2z+4=-2y-z-5, group common terms:
5y+3z=-9
similarly, using i and ii, eliminate x:
i) 2x – 3y – 2z = 4
ii) x + 3y + 2z = –7
multiply the second equation by 2:
i) 2x – 3y – 2z = 4
ii) 2x + 6y + 4z = –14
thus 2x=3y+2z+4 from i and 2x=-6y-4z-14 from ii:
3y+2z+4=-6y-4z-14
9y+6z=-18
So we get 2 equations with variables y and z:
a) 5y+3z=-9
b) 9y+6z=-18
now the aim of the method is clear: We eliminate one of the variables, creating a system of 2 linear equations with 2 variables, which we can solve by any of the standard methods.
Let's use elimination method, multiply the equation a by -2:
a) -10y-6z=18
b) 9y+6z=-18
------------------------ add the equations:
-10y+9y-6z+6z=18-18
-y=0
y=0,
thus :
9y+6z=-18
0+6z=-18
z=-3
Finally to find x, use any of the equations i, ii or iii:
<span>2x – 3y – 2z = 4
</span>
<span>2x – 3*0 – 2(-3) = 4
2x+6=4
2x=-2
x=-1
Solution: (x, y, z) = (-1, 0, -3 )
Remark: it is always a good attitude to check the answer, because often calculations mistakes can be made:
check by substituting x=-1, y=0, z=-3 in each of the 3 equations and see that for these numbers the equalities hold.</span>
Pls. see attachment. I created that table for easy monitoring and understanding.
Yellow cells are sums that are even.
Orange cell are sums that are multiples of 3.
Yellow cells w/ orange texts are sums that are both even and multiples of 3.
The GDP of the country for 2014 is $5.3196 × 10⁸.
<h3>What is multiplication?</h3>
Multiplication is the process of multiplying, therefore, adding a number to itself for the number of times stated. For example, 3 × 4 means 3 is added to itself 4 times, and vice versa for the other number.
Given the Gross Domestic of a country in the first quarter of 2014 was $1.3299×10⁸. Therefore, the GDP of the country for that year will be,
GDP = 4 × (Gross Domestic for a single quarter)
= 4 × ($1.3299×10⁸)
= $5.3196 × 10⁸
Hence, the GDP of the country for 2014 is $5.3196 × 10⁸.
Learn more about Multiplication:
brainly.com/question/14059007
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Answer:
A group of seven friends each received one-half of a pound ofcandy. How much candy did they receive total?✓
0.5 pounds x 7= 3.5 poundsStep-by-step explanation:
