First and third, second can still be simplified.
Answer:
x = 46°
Step-by-step explanation:
the opposite angles of a cyclic quadrilateral are supplementary, sum to 180° , then
x + 134° = 180° ( subtract 134° from both sides )
x = 46°
There are 2 x intercepts, x=-4 and x=-1
In short, for a vertical parabola, namely one whose independent variable is on the x-axis, usually is x², if the leading term coefficient is negative, the parabola opens downward, and its peak or vertex is at a maximum, check the picture below at the left-hand-side.
and when the leading term coefficient is positive, the parabola opens upwards, with a minimum, check the picture below at the right-hand-side.