Seven more than three times a number is twenty-five

Both the red and blue line segments stretch from the center of the circle to a point on the circle. the length of the blue segment is 5. how long is the red line segment?

Given: hf || jk; hg ? jg prove: fhg ? kjg to prove that the triangles are congruent by asa, which statement and reason could be used as part of the proof? fgh ? kgj because vertical angles are congruent. jkg ? hfg because vertical angles are congruent. fhg ? jkg because right angles are congruent. hfg ? kjg because alternate interior angles are congruent.

What is the number 321,000,000 in scientific notation? also what is the number? ?