First, we need to rewrite the equation in the standard quadratic form, ax2+bx+c=0. In this case, the variable is f. −7f2+11f+9=4−3f Add 3f to both sides: −7f2+11f+3f+9=4−3f+3f −7f2+14f+9=4 Subtract 4 from both sides:
−7f2+14f+9−4=4−4 −7f2+14f+5=0 Now we have a quadratic equation in the form af2+bf+c=0, where a=−7, b=14, and c=5. We can solve for f using the quadratic formula: f=2a−b±b2−4ac Substituting the values of a, b, and c: f=2(−7)−14±142−4(−7)(5) f=−14−14±196+140 f=−14−14±336 f=−14−14±16×21 f=−14−14±421 f=1414∓421 f=1∓7221 Now we find the two solutions:
f1=1+7221≈1+72(4.58)≈1+79.16≈1+1.3086≈2.31 f2=1−7221≈1−72(4.58)≈1−79.16≈1−1.3086≈−0.31 So the two solutions, rounded to two decimal places, are 2.31 and −0.31.