Answer:
x = 9 or x = -9
Step-by-step explanation:
The parameters of the given points are;
The location of the point T = (0, 7)
The location of the point U = (x, -5)
Then distance between points T and U = 15 units
The distance between points A and B, 'd', given their coordinates, A(x₁, y₁) and B(x₂, y₂) is found using the following formula;
[tex]d=\sqrt{\left (y_{2}-y_{1} \right )^{2}+\left (x_{2}-x_{1} \right )^{2}}[/tex]
Therefore, for the given points, T(0, 7) and U(x, -5), we get;
[tex]15 = \sqrt{\left ((-5) - 7 \right )^{2}+\left (x - 0 \right )^{2}}[/tex]
Squaring both sides, gives;
[tex]15^2 = \left ((-5) - 7 \right )^{2}+\left (x - 0 \right )^{2}} = (-12)^2 + x^2[/tex]
∴ x² = 15² - (-12)² = 81 = 9²
x² = 9²
∴ x = ±√(9²) = ± 9
The possible values of x are x = 9 or x = -9
