Prove algebraically that the straight line with equation x=2y+5 is a tangent to the circle with equation x^2+y^2=5 I have 4/5 marks. Can anyone tell me how to achieve the 5th mark?

this is equal to zero, then we know that the equation has only one solution. so b2 - 4ac = (4)2 - 4(1)(4) = 16 - 16 = 0.

one of each metals

step-by-step explanation:

definition: a circle is the  set of all points in a plane that are equidistant  from a given  point  called the center of the circle. we use the symbol ⊙ to represent a circle. the a line segment from the center of the circle to  any point  on the circle is a radius of the circle.

step-by-step explanation:

i googled it and this is what i got i don't know how it is. sorry.