Answer:
7
Step-by-step explanation:
2x² - 28x + 98 = 0
x² - 14x + 49 = 0
(x - 7)² = 0
x = 7
7x + 4 = 9
7x + 4 = 19
2x = 19 - 4
7x = 15
x= 15 – 7