It's best to write the two equations as a vertical column:
8x+14y=4
-6x-7y = -10
Note that if we multiply the 2nd equation by 2, we get -12x - 14y = -20. The reason for wanting this version of the 2nd equation is that its -14y cancels the +14y in the first equation:
-12x - 14y = -20
8x+14y=4
Combine these equations, column by column. We get -4x = -16, which results in x = 4. Now find y by subbing 4 for x in either given equation. If we use the first equation, we get 8(4) + 14y = 4, or 32 + 14y = 4, or 14y = -28. Then y = -2.
The solution to this system of linear equations is thus (4,-2).
Check this result by substitution of these coordinates into -6(4) - 7y = -20:
-24 - 7(-2) = -10. Is this true or not?
-24 + 14 = -10 is true. Thus, (4,-2) is the desired solution.
The solution to your Q is got to be 9t=6.3
For twice a number we can use the variable x
For four times a number we can use the variable c
4c - 2x + 15
I believe this is correct although I'm not 100% sure
<h2>
Answer:</h2>
The radius of the cone is:

<h2>
Step-by-step explanation:</h2>
The total area of cone is given by:

where r is the radius of the cone and l is the slant height of the cone.
and the lateral area of cone is given by:

Hence, from equation (1) and (2) we have:

i.e.

i.e.

The -1 means that y = -1, so point is one unit below the x-axis. In (5, -1), the x is positive, which could put the point in either the first quadrant or the fourth. With the y being negative, however, it means that the point is in the fourth quadrant. Those are your 2 true statements.