The straight line joining the points A(3,-5) and B(6,k) has a gradient of 4.
Gradient is the slope
So the slope of the line joining the points A(3,-5) and B(6,k) is 4
Slope of line joining two points = 
A(3,-5) and B(6,k) are (x1,y1) and (x2,y2)
slope = 
slope = 
We know slope =4

Cross multiply and solve for k
k + 5 = 12
k = 7
The value of k = 7
Solve the following system using elimination:
{7 x + 2 y = -19 | (equation 1)
{2 y - x = 21 | (equation 2)
Add 1/7 × (equation 1) to equation 2:
{7 x + 2 y = -19 | (equation 1)
{0 x+(16 y)/7 = 128/7 | (equation 2)
Multiply equation 2 by 7/16:
{7 x + 2 y = -19 | (equation 1)
{0 x+y = 8 | (equation 2)
Subtract 2 × (equation 2) from equation 1:
{7 x+0 y = -35 | (equation 1)
{0 x+y = 8 | (equation 2)
Divide equation 1 by 7:
{x+0 y = -5 | (equation 1)
{0 x+y = 8 | (equation 2)
Collect results:
Answer: {x = -5, y = 8
Because this is a second degree equation you will have 2 solutions. When you take the square root of a number you have to account for both the positive and negative roots. Since the square root of 289 is 17 then your solutions are +17 and -17.
Answer:
B the function is nonlinear
Step-by-step explanation:
Proportional reasoning is a form of mathematical reasoning that involves a sense of co-variation and of multiple comparisons, and the ability to mentally store and process several pieces of information. I hope my answer has come to your help. God bless and have a nice day ahead!