What is the distance between point (7,9) and point (-2,7)

Iwant to know what 3g+5h+4g-2h is my teacher is too selfish to tell us

Which of the following describes the graph of y--4x-36 compared to the parent square root function? stretched by a factor of 2, reflected over the x-axis, and translated 9 units right stretched by a factor of 2, reflected over the x-axis, and translated 9 units left stretched by a factor of 2, reflected over the y-axis, and translated 9 units right stretched by a factor of 2, reflected over the y-axis, and translated 9 units left save and exit next submit

The distance of a chord from the centre of a circle is 12cm and the lenght of the chord is 10cm. find the radius of the circle