Answer:
[tex]\implies \dfrac{80}{90}-\sqrt{50} \times 19^2 \div 23^2[/tex]
Order of operations (PEDMAS)
Following the order of operations,
Carry out the exponents (and radicals) first:
[tex]\implies \dfrac{80}{90}-\sqrt{25 \cdot 2} \times 361 \div 529[/tex]
[tex]\implies \dfrac{80}{90}-5\sqrt{2} \times 361 \div 529[/tex]
Now the multiplication and division (from left to right):
[tex]\implies \dfrac{8}{9}-1805\sqrt{2} \div 529[/tex]
[tex]\implies \dfrac{8}{9}-\dfrac{1805\sqrt{2}}{529}[/tex]
Convert the fractions so that their denominators are the same:
[tex]\implies \dfrac{8 \times 529}{9 \times 529}-\dfrac{1805\sqrt{2} \times 9}{529 \times9}[/tex]
[tex]\implies \dfrac{4232}{4761}-\dfrac{16245\sqrt{2}}{4761}[/tex]
Answer as a fraction:
[tex]\implies \dfrac{4232-16245\sqrt{2}}{4761}[/tex]
Answer as a number:
[tex]\implies -3.936546801... = -3.9\: \textsf{(nearest tenth)}[/tex]